Radio

Introduction

Bluetooth™ is a revolution in wireless technology specially short-range digital communication among computing and communications devices. It is a latest wireless communication technology for exchanging data over short distances, and is an attempt to get rid of computer’s jungle of wiring. Using a special radio frequency to transmit data, it creates a short range network. It is very secure and can connect up to eight devices. Bluetooth wireless technology enables robust, secure, wireless connections between portable and fixed devices. So the main features of Bluetooth technology are robustness, low power, and low cost. Bluetooth can improve in any short distance communication system like medical instrument, end to end data transfer etc. It has high mobility which means it can be moved anywhere, long life battery which means it lasts longer than any other equipment and it has no infrastructure to support model.

This project consists of building a remote health monitoring system which provide a autonomous system for regular patients. The project is designed to meet its aim to provide a plug-and-play system which run over router and transmit data through Bluetooth. A Bluetooth adaptor will be built whose has input from Bluetooth and output via Ethernet/Wireless device. The Tele-health (TH) technology has invented so many systems so far which are helping patients cope, manage and improve their health condition. It has been also used to reduce the workload of healthcare practitioners specially for those patients whose need to visit practitioners regularly basis. However, current TH systems often require patients to actively interact with the technology and this is major drawback of all current TH technologies. “The reason being that the elderly patients who are suffering from chronic condition, may find it difficult to interact with new TH technologies. Therefore, our proposal aims to provide a plug-and-play system which permits all ever-present connectivity between different components of the TH system with requiring minimal input from patients”.

As stated before, this project intends to develop an end-to-end TH system that permits monitoring and feedback solution which uses every-possible technology, e.g: mobile phone technology (GSM, 3/4G), IEEE (Institute of Electrical and Electronic Engineers) Bluetooth Wi-Fi, xDSL (Broadband) communication standards and even in POTS (Plain Old telephone service) as well. “Furthermore, an automatic feedback mechanism on the reading of patients’ health parameter will be embedded in the system. Thus, if a location has limited or no mobile phone network coverage, especially in rural areas, then the access point approach to data transmission would be adopted”.

Currently, there are already so many TH systems exist in the market. TH system currently developing and different health organizer are adopting new TH systems. Moreover, so many universities are researching about new technologies TH systems. Let’s consider a scenario where this TH system would be use for: With this TH system, patients will take their blood pressure measurements at home using a Bluetooth enabled or adaptable specific kind of monitoring device. In this project, an extra mobile will take place instead of that monitoring device which is enable to send the reading of specific measurement, taken by patients. This mobile is Bluetooth enabled and have a special designed software that helps to connect another Bluetooth enabled device (patient mobile) and transmits data to that device. The patient mobile is a remote device that uses for building connection with PC and whatever data come from the first mobile (monitoring device), passes to PC automatically. The patients mobile also capable to receive any feedback from the doctor as well. The PC works as an end-to-end device in this project which is connected with internet. The PC is capable and send any data received from patient mobile to a particular email address. The whole mechanism will be designed and build to transmit and response automatically. On the other hand, The doctor receives readings of a particular patients and send the feedback for that readings via PC and Internet. The patient mobile has a special kind of software which is enable to receive a feedback coming from the doctor. The whole system is represented graphically in figure 1.

Aim

The aim is to design and build a plug-and-play Bluetooth interface (within laptop) that connects Bluetooth enabled phones with a doctors surgery using a designated patients email address. The patients phone sends his/her latest results using Bluetooth to the interface which then sends an email to the surgery. This avoids expensive text messaging (multiple users increase cost). The doctor then has daily information on patients condition allowing them to make more appropriate decisions regarding their healthcare. It importantly also allows patients to carry on their daily life as normal, knowing that their latest results are being considered rather than intermittent results while visiting the doctors surgery.

Although this work is demonstrated using Wi-Fi, it could easily be done with a simple ADSL modem connection via a network cable. The system works in both equally. What’s important is that there is an internet connection and a PC within the home or a phone with internet connection.

Objectives

1. To do background reading and investigation about Bluetooth technology, Ethernet/IEEE standard 802.11 and Wi-Fi modem.
2. To design a Bluetooth interface which makes connection between two Bluetooth enabled mobiles and a PC.
3. To construct a Java program using J2ME for first mobile (monitoring device) to create a connection with second mobile and sending message over that phone.
4. To construct a Java program using J2ME for second mobile (Patients mobile) to form a bridge connection between first mobile and PC to transmit data via that mobile.
5. To construct a Java program using Java SE for PC to create connection with webmail server and send data in that mail address automatically.
6. To test the connections using two mobiles and check for errors and limitations.
7. To build a PC application using Java SE to give feedback from that webmail server remotely to any mail server.
8. To construct a mobile application using J2ME for second mobile to have access in an inbox of a mail address to receive a feedback.
9. To test PC application and mobile application and check errors and limitations.
10. To integrate and test whole interface and all programs.
11. To investigate the limitation and problems of the whole system and find solutions about them.
12. To investigate the implementation of that Bluetooth interface for future purposes.

Deliverables

Project arrangement form:

To be completed by Friday 8th October 2010

Interim Report:

This report explains the aims and objectives of this project. The requirement for the project and planned technical approach also is included. This report will be submitted by Friday 5th November 2010 and received feedback from supervisor by Friday 19th November 2010.

Draft Final report to supervisor:

A draft version of the final project report must be submitted for feedback to the supervisor by Friday 25th March 2011.

Final project report:

Final Project e-Report must be submitted by Tuesday 3rd May 2011 through TURNITIN for plagiarism checking and Final Project Report and log book must be submitted to Faculty office by Thursday 5th May 2011 as mentioned in the Unit Guide.

Project Viva and Presentation:

Project Viva and Hardware/software Demonstrations will take place in 2nd Semester Examination Period.

Constructed Hardware/Software:

This project contains both hardware and software part which need constructed. A network adaptor need to design and build and a program which support this adaptor need put together as well.

Technical Background and Context

Bluetooth

The term Bluetooth TM refers to an open specification for a technology to enable short-range wireless voice and data communications anywhere in the world. Bluetooth technology also uses radio waves like all other communication medium. Bluetooth technology sends information within your own personal space, which is called Personal Area Network (PAN) at distance up to 10 meters. Now-a-days every single communication device has Bluetooth built-in.

The Bluetooth Special Interest Group (SIG) has produced an open specification for Bluetooth wireless communication. The reason behind being open specification, this is publicly available and royalty free. To help advance extensive acceptance of this technology, an open specification has been a primary objective of the SIG (The explanation of SIG will be later on).

Bluetooth technology is a short-range communication technology that is simple, secure, and everywhere [3]. It is planned for replacing the cables connecting devices. It also maintains high level of security. That’s why Bluetooth wireless technology is widely accepted by public so much that this technology is built into a wide range of products, from cars and mobile phones to medical devices and computers. With Bluetooth technology, these devices can communicate without having any wire over a single air-interface, using special kind of radio waves or frequency to transmit and receive data. So Bluetooth is a way of exchanging data wirelessly over short distances, and is an attempt to do away with your computer’s jungle of wiring. Bluetooth is a piece of hardware or a small computer chip that contains the Bluetooth radio, and some software that lets the users, connect devices using Bluetooth technology. That’s why Bluetooth is very cheap and a very small sized chip which can fit in any kind of device. Even with Bluetooth technology, making connections is as easy as just powering up the device.

“The Bluetooth radio transceivers operate in the globally available unlicensed ISM radio band of 2.4 GHz. The ISM (Industrial, Scientific, and medical) bands include the frequency ranges at 902 MHz to 928 MHz and 2.4 GHz to 2.484 GHz, which do not require an operator’s license from a regulatory agency”.

Now, the question arouse: why do we need one more wireless technology By comparing all other existing wireless technology with Bluetooth, it can be much more clear about why we need one more wireless technology where there is so many successful wireless technologies. It is also going to give much more details about Bluetooth technology.

If infrared and Bluetooth devices can support many of the same applications, why do we need both technologies Infrared transceiver must need to see each other “eye to eye” and devices must be in a few feet apart, otherwise transmission will fail. Bluetooth overcomes the distance limitation by having a nominal range of about 30 feet (as stated above). Another sense is Bluetooth works like radio, so transmissions are Omni-directional. Bluetooth can penetrate solid objects and its capability to communicate with other devices in a network called “piconet” allows for data exchange opportunities that are very hard or impossible with infrared. When it comes to data transfer speed, Infrared can transmit data at very high speed of 4 Mbps while Bluetooth can only at 721 Kbps though new versions of Bluetooth technologies are coming.

Now 802.11b (wireless LAN) is to connect large devices that have lots of power at high speed typically 11 Mbps within distance of 300 feet. Though less distance and transmit speed, Bluetooth is to connect peripherals like PDAs and mobile phones and consume less power 500 times. So it’s not definitely replaced by 802.11b (wireless LAN). 802.11b (wireless LAN) can’t be use instead of Bluetooth for transmitting between peripherals. The radio uses 2.5 mW of power. Bluetooth has been designed to have very low power consumption.

The Bluetooth Special Interest Group (SIG)

As previously described, Bluetooth wireless communication is personified as a technology specification. The body manages the development of Bluetooth standards and the licensing of the Bluetooth technologies and trademarks to manufacturers is called the Bluetooth Special Interest Group (SIG). The Sig is a privately held, not-for-profit trade association founded in September 1998. There was no Bluetooth SIG headquarter or no Bluetooth corporation or any sort of legally incorporated entity until 2001. The SIG built-in and is now officially recognized as the Bluetooth Special Interest Group, Inc in February 2001. Now the SIG is headquartered in Kirkland, Washington with Michael W. Foley presently its executive director. Currently the SIG is comprised of more than 14000 member companies. The SIG has local offices in Hong Kong, Taiwan, China, Korea, Japan and Sweden. The SIG depends upon the contributions and participation of its member companies. Clearly a major task of the SIG has been to develop the specification, but other SIG activities include joint work with other consortia and standards and regulatory bodies, educational and promotional events such as developers’ conferences and the definition of a testing and certification process.

Bluetooth technology was visualized by engineers at Swedish telecommunications manufacturer Telefonaktiebolaget LM Ericsson who realized the necessary of global short-range wireless communication. In 1994 Ericsson had begun a project to study the feasibility of a low-power, low-cost radio interface to eliminate cables between mobile phones and their accessories. The Bluetooth SIG was formed to focus on developing open specification by the leading companies in computing and telecommunication in early 1998. The founding companies of the SIG are Ericsson, Intel Corporation, International Business Machines Corporation (IBM), Nokia Corporation and Toshiba Corporation. These companies formed the original core group of the SIG, actually known as promoter companies.

History & the name Bluetooth

“The engineers at Ericsson code named the new wireless technology Bluetooth to honor a 10th century Viking king in Denmark. Harald Bluetooth reigned from 940 to 985 and is credited not only with uniting that country, but with establishing Christianity there as well” [4]. Harald name was actually Blatand, which roughly translates in English as “Bluetooth”. It seemed perfect to the SIG founders to name the organization that was intended to unify multinational companies after a Scandinavian kind who united countries. Thus the Bluetooth name was initially an unofficial code name for this project but today has become the trademark name of the technology and the SIG. Figure 2 is showing the logo, inspired by the initials “H B” for Harald Bluetooth.

In 1994, Ericsson Mobile Communications, the global telecommunications company situated in Sweden, initiated a study to investigate the feasibility of a low-power, low-cost and wireless interface between mobile phones and their accessories. The main aim of this study was to find a way to get rid of the cables between mobile phones and their accessories.

Reference

1. Dr. S. Dudley-Mcevoy, “Proposal for Synchronous Patient Reinforcement Incorporating Tele-medical Environment (SPRITE)”, London: London South Bank University, November 2010.
2. B. A. Miller, C Bisdikian. Bluetooth Revealed, 2nd edition. New Jersey: Prentice Hall, 2002.
3. Bluetooth SIG, “Bluetooth specification”, online, available from: http://www.bluetooth.com. [accessed 12th APR 2011]
4. N. J. Muller. Bluetooth Demystified. New York: McGraw-Hill Telecom, 2001.
5. Wikipedia, “Bluetooth Special Interest Group”, online, available from: http://en.wikipedia.org/wiki/Bluetooth_Special_Interest_Group. [Accessed 13th APR 2011]
6. N. Eddy. Bluetooth SIG adopts Low Energy Version 4.0, eWEEK Europe UK, 2010. [Online] Available from: http://www.eweekeurope.co.uk/news/bluetooth-sig-adopts-low-energy-version-40-8224 [Accessed 14 APR 2011

Abstract

Signal generators also know as function generator or test oscillator, have come to be more popular and most used testing device for the engineers especially and also for the medical sector. Signal generator delivers an accurate calibrated range. It provides a signal that can be adjusted according to the frequency, output voltage, impendence, waveform and modulation. It has been in existence and they are used in so many ways before time till present. An American inventor Nikola Tesla has conveyed electricity from one location to another in the form of signal and uses the same frequency.

This report talks about the overview of a signal generator, how they do function using their applications and also describe to us their operating principles using the direct digital synthesis DDS, their types and designs. The Next page gives you a brief introduction about the early days of signal generator and how they are been used in those days.

Introduction

Before the Initiation of this device called signal generator which is around 1906 to 1920 are regarded to be the early days of radio, the only way for testing of new apparatus or electronic instrument was to use another similar device to create the signal, which was the case of new tools and modulation format in radio. During that time, this basic method of testing worked excellently with minimum percentage errors, but problem arises when there is a circumstance whereby they might be diverse devices under test. To solve this problem, there must be need for so many reference devices. One radio’s was picked which was used as a performance parameter and was measured which was now used as the standard or “golden radio” as it has been called.

Even if they are expensive, a regular change in their functioning features either during a short time as a result of warming up or during a long time as an effect of continued use, and for this reason their will be reduction in their accuracy. The need for signal generator that can effectively used to test devices as the field of engineers must be to reduce this flow.

However, we are going to explain the device “signal generator” in this report and also we will discuss about the operating principles, and also the things I have already mention in the abstract area. In this next page, we will be looking at the overview of this device signal generator.

­Signal generator (outline and types)

A signal generator also called a function generator or a text signal generator is an electronic device designed to perform a variety of operations which includes band pass filter characteristics, the response of amplifiers to frequency or fault tracing in many electronic equipment and circuits. “Signal generator is a tool widely used in fields such as industrial electronic instrumentation, medicine, production, communication and research”, (Alloca and Stuart, 1983).

A signal generator is the stimulus source that pairs with an acquisition instrument to create the two elements of a complete measurement solution. In its various configurations, signal generator can provide stimulus signals in the form of analog waveforms, digital data patterns, modulation, noise and it may add known, repeatable amount and types of error (distortion) to the signal it delivers. Signal generator can produce the most types of waveforms or signal which are square waves, sine waves and triangular waves over a wide range of frequency. Coombs, (1972) declares that the frequency range of a signal generator maybe less than 1Hzto at least 1MHz. Some other type of signal generators, have the ability to produce pulse, trapezoid and ramp waveforms including the ones mention above. Therefore, there are many types of signal generator designed to a variety of uses which has much possible application meaning that one particular type of signal generator may not be suitable for all purposes.

Here are the two main type of signal generator

1. Arbitrary waveform generator
2. Function signal generator

Below is a picture example of a typical function generator:

Arbitrary waveform generator

Arbitrary waveform generators (AWG) are complicated playback system that delivers waveforms based on stored digital data that describes the regularly changing voltage levels of an AC signal. The arbitrary waveform generator can produce any kind of waveform you can think of. You can use many methods to create the needed output (from mathematical formulae to drawing the waveform).

Function signal generator

Function generators are more simple compare to arbitrary waveform generator. They generate simple signal in wave form and this signals are been produce by a circuit which creates the repeating wave which is usually a sine wave. They are most often use in process of designing or repair simples electronics.

Design of signal generators

Before the modern waveform generators were initiated, analog was the mode of operation. In some industries, analog refers both to the circuit technique used to generate signals and to the signal themselves. Functionality, economic feasible, and types of waveform needed have really change the design of signal generator in period of times, although the traditional analog signal generators still exist till date. The analog is a means to represent a material measure, for instance an indicator on a current meter (regulator), by a quantity whose measurement is known. Such measurements, do not really give the accurate result of a particular tool or device under test, as they are prone to having drifts in their working parts.

Most modern signal generators are based on the digital technologies such as the modern function generators which uses a technology known as Direct Digital Synthesis (DDS) which are able to provide a wide range of signal or waveform. The DDS device are more like to generate analog signals via creating a digital output signal that is continuously pulsed by a clock signal and at last translating the digital signal to form an analog signal. Below is the experimental diagram of this process.

The Method above, illustrate that the input is supplied into the 8bit counter which evaluate the input with an analog, (Q5 to Q0). The matching analog now is been verified with an already stored address which is the ROM (Read Only Memory) 256 x 8. As the counter cycles through the 256 different addresses, which the ROM has for each analog, the ROM counter now picks out a digital value corresponding to that address which sequentially represents the input. This information is then processed and outputs the 256 data points to the DAC (Digital to Analog Converter) which is the 8bit converter. The analog signal obtain is then shown as a waveform. An example of a generator that uses this method illustrated above is the 20MHz sweep function generator from BK Precision (model 4040DDS) image is shown below.

According to BK Precision (2010), this sweep generator is a full featured DDS generator, the unit generate superb quality waveforms with a high signal precision and stability and it provides sine and square wave outputs over the frequency range from 0.1Hz to 20 MHz in one extended range. Most of the DDS generator today are dedicated instrument, simple and comfortable, and are at low cost from a few tens of dollars to tens of thousand of dollars. In the next section, we are going to look at how this device operates.

Operating principles of signal generator

In this 21st century, most of the modern function generators use Direct Digital Synthesis (DDS) technology to generate output wave forms. BK Precision sweep function generator (model 4040DDS) happens to be among one of this generators. This section describes how DDS technology works. There are two fundamental ideas of DDS technology which includes:

Producing an arbitrary waveform that can be in various waveforms or not assigned a particular value from a periodic ramp signals.
Producing a digital ramp.

First, consider producing wave function that can be in various waveforms or not assigned a particular value from a periodic ramp signal. To make this explanation more simple and understandable, imagine the ramp period (t) is greater than or equal to 0s (t ? 0), then lets call the recurring ramp function R(t) as shown in the diagram below.

This ramp function R(t) as shown in figure 1 differs linearly or oscillate between 0 and 1 with period T. Now, suppose their is a new function F(t) that is defined on the interval 0? t ?1, in mathematical terminology, the domain of the function which is the values assigned to the independent variables of F(t) is the half-closed interval. Imagine to construct another wave function of period T which is similar to R(t) with the shape of F(t) and assuming again that the period is 4s using the diagram shown in figure 4, we will notice that as the time increases from t0 to t4, which is equal to one period, there is a sequence which implies that their will be a gradual rise in the function until t4, therefore calculating the corresponding value of each time and removing the integer part of it. The calculation for t0 to t8 is shown in the table below using the figure 4 diagram.

The illustration shows that there is a rise in the time value, in the sense that when one period is reach, it will start over again until another period is reached. This is how it works continuously for the defined time interval. This means that it resets after each successive cycle.

On the other hand, the resetting of the time interval is carried out by a phase accumulator which is the first time interval that is the t1 = frequency. In the above example, the waveform that was created has a frequency of 0.25Hz and a phase angle of 90 that means the frequency is x360

As BK precision (2010) guild book instruct that to produce a digital ramp, as an alternative of increasing the time intervals by 1s, let the increment be in terms of ?, the phase angle, by the digital clock and for an N-bit counter, it will count from 0 to 2N – 1, then reset to 0 again. For example, let the value of be N = 4, which will be (24), therefore the counter result is 16 bits. When a signal is received, it will only match up to one of the bits frequencies and the waveform of that frequency will be generated.

Lastly, the generated waveform might be displayed as a square or triangular signal using the control buttons on the device. This is made possible by including an operating amplifier (op-amp) in the circuit. Assume the received input signal was a sine wave, it can be converted to a square waveform; an op-amp acts as a comparator that gives and output signal of “1” only when the amplitude of the sine wave is greater than 0 and a “-1” when the amplitude is less than 0. According to Floyd (2009), this change was essential because digital data processing and transmission can be more effective and dependable than analog data and it’s of advantage when data storage is needed.

Functions and applications

Signal generators have hundreds of different applications and function that are suited for variety of use in many fields but in electronics measurement context, they fall into three basic types:

Verifications
Characterization
Stress and margin testing

Verification

In the world of electronic and technologies, wireless equipment designers that are building new transmitter and receiver hardware must stimulate baseband I and Q signals (with or without impairments), to verify some wireless standards, a high performance arbitrary waveform generators can provide the needed low-distortion, high-resolution signals at rates up to 1GB/secs.

Characterization

This is a state whereby the newly developed digital to Analog converter (DAC) and the Analog to digital converters (ADC) must be systematically tested to determine their limits of undeviating, distortion and so on.

Stress and marging testing

Advanced signal generators, save the engineers hours of calculation by providing efficient built- in jitter editing and generation tools because engineers that works with the serial data stream architectures; commonly used in digital communications buses and disk drive amplifiers, need to stress their devices with impairment especially jitter and timing violations so engineers must characterize their emerging designs to ensure that the new hardware meets design specifications across the full range of operation and more.

However, using this device, much difficulty in electronics and also field like the medicine can now be resolute easily.

To design an assorted signal and a high speed low filter data, an arbitrary waveform generator can be used. They are specifically design for it.
Radio frequency signals are used to achieve tests on radio transmitters and receivers. (Theraja and Thereja, 1959)
Signal generators that are connected to oscilloscopes can be use in testing faults in electronic equipment and devices.
In telecommunications today phones functions using signals, for example: the process, transmit and receive data.
Devices for example: digital X-ray appliances, brain mapping system and advanced cardiology uses signal in most medical field today.

Conclusion

The modern DDS generators have some advantages and disadvantages of it depict that they help in solving solutions in various fields. Describing about the advantages of DDS, you discover that their frequency is tuneable with sub-Hertz resolution; their phase angle is digitally adjustable, as long as the clock is stable, they don’t go with the flow due to temperature changes or aging of components, addition of arbitrary waveform generator is not theoretically difficult and lastly they have simple design and low parts count which help to keep cost down.

However, describing the disadvantages of this machine has to do with the negative aspect which is their output frequency is ? ? the clock frequency, their amplitude is also fixed that is; they need external circuitry to change, sine wave is sampled and not spectrally pure; distortion is present at that moment. But this disadvantages, does not cost more harm the technology is still the best and with more careful design in future, these advantages can me minimized.

References

Floyd, L. (1977) Digital Fundamentals. 10th Edn. Upper Saddle River, New Jersey: Pearson Education
Ifeachor, E. and Jervis, B. (2002) Digital Signal Processing. A Practical Approach. 2nd Edn. Harlow, England: Pearson Education
Hill, A. (2010) What is signal generatorAvailable at: http://www.wisegeek.com/what-is-a-signal-generator.htm (Accessed 15 March 2011.)
Nashedky, B. (1996) Electronic Devices and Circuit Theory. 6th Edn. Englewood Cliffs, New Jersey: Prentice-Hall.
Peterson, D. and BK Precision (2010) Function Generator and Arbitrary Waveform Generators Guidebook. Available at: http://www.bkprecision.com/support/downloads/guides/Function_and_Arbitrary_Waveform_Generator_Guidebook/BK-Function-Generator-and-AWG-Guidebook.pdf. (Accessed: 25 March 2011)
Alloca, J. and Stuart, A. (1983) Electronic Instrumentation. Reston, Virginia: Prentice-Hall.
Crecratf, D. et al (1990) Analogue and Digital Electronics. Great Britain: The Open University
Referencec.com (2010) Signal generators. Available at: http://www.reference.com/browse/signal+generator (Accessed: 14 April 2011)
Theraja, B. And Theraja, A. (1959) A Textbook of Electrical Technology. 23rd Edn. Reprint 2003. Ram Nagar, New Delhi: S. Chand & Company Ltd.
Coombs, C. (1972) Handbook of Basic Instrumentation. New York: Mc Graw-Hill
Yourdictionary.com (2010) Nikola Tesla Biography. Available at: http://biography.yourdictionary.com/nikola-tesla (Accessed 18 April 2011)
Tektronics (2008) Signal generator fundamentals Guidebook. Available at: http://circuitslab.case.edu/manuals/Signal_Generator_Fundamentals-_Tektronix.pdf (Accessed 20 April 2011)
ZTech Instruments (2010) Waveform Generator Fundamentals. Available at: http://www.ztecinstruments.com//applications/waveform-generator-fundamentals.php (Accessed: 6 April 2011)

1. Name and Address of the applicant: 2. Particulars of the aero-mobile Licence, if any, already held : 3. Particulars of Aircraft in respect of which a licence is required. a) Call Sign: b) Name and Type of Aircraft: c) Name of owner: d) Passenger or Freight Aircraft: e) Normal Route: f) Place of Registry (an attested copy : of certificate of Registration to be attached) 4. State whether the Radio Installation is provided in pursuance of statutory equirements or otherwise (i.

e. , compulsory fitted or non-compulsory fitted). 5. Nature of Service performed: 6. Description of apparatus for which the licence is applied for: Radio Communication Transmitters Manufacturers TypeOutputFreq.RangeEmissionFrequency Rated (kHz)Tolerance Power (Watts) Main Standby Radio Communication Receivers Manufacturers Type Frequency. Range Main Standby Radio Navigation Apparatus Manufacturer Type Frequency.

Range i) Automatic Direction Finder (ADF) ii) Instrument Landing System (ILS) a) Localizer Receiver b) Glidepath Receiver ) Maker Receiver iii) VOR Receiver iv) DME Interrogator v) ATC Transponder vi) Weather Radar vii) Radio Altimeter viii) Loran Receiver ix) x) Certificate of Inspection (Must be completed by a competent Wireless Telegraph Engineer) It is certified that the Radio Apparatus detailed here in before has been satisfactorily installed/and the particulars given thereof are correct. Dated:Signature of the certifying Engineer Name_______________________ (in block letters) Address:Designation (SEAL) DeclarationI hereby solemnly declare and say that foregoing facts are true and correct and nothing is false there in and no material has been concealed therefrom. I also agree that in case any information given by me herein before is found false at a later date, the licence, if granted, will be cancelled. I further solemnly given an undertaking that the apparatus described here-in-before will be worked in accordance with the conditions of the licence and operators holding approval certificate of proficiency shall only be employed to work the said apparatus Place:Signature of Applicant Dated:Name _______________________ in block letters) Designation___________________Note : This application duly completed should be forwarded to the Wireless Advisor to the Government of India, Ministry of Communications, Sardar Patel Bhawan, Parliament Street, new Delhi-110 001 (through Director General of Civil Aviation, Technical Centre, Opp. Safdarjung Airport, New Delhi) Rate of fees : The rate of fees per station per annum is Rs. 250/- Manner of Payment : The fees may be paid through a crossed band Draft drawn in favour of Pay and Accounts Officer (HQ), Department of Telecommunications, payable at State Bank of India, New Delhi.

ABSTRACT:

Today, there is a large number of mobile user groups and In that, the need of service of mobile user group plays a great dispute on the utilization of bandwidth. The radio frequency spectrum is an inadequate resource, to improve service quality and system capacity radio spectrum should be carefully planned. Research is carried out to improve system capacity and service quality. Admission capability is highlighted by the system capacity and the service quality relates to the connection continuity. This proposal reveals the impact of protection, which is used to improve the strength of the capacity of cellular mobile systems. Traffic model is established by using the mobility characteristics of the real world. The relation between admission capability and channel reservation is given by the markov’s approach. The proposed dynamic reservation scheme is proposed to provide handoff coordination between the service quality and system capacity.

INTRODUCTION:

The evolution of cellular mobile systems began with the first generation (1G) cellular systems introduction, and pass on through second generation (2G) and continuing third generation (3G ), featuring the development into the fourth generation (4G) systems. This generation systems are divided based upon the coding, modulation, and multiple access techniques which are used.

First public mobile telephone system (MTS) began operation in 25 American cities. In this system contains an efficient transmitter on tall building with in the city and the permanent single channel is assigned to mobile cellular phone for sending and receiving data through the concept of push-to-talk. Late 1960s, improved MTS(IMTS) implemented and dual channels for sending and receiving the data. In the starting of cellular mobile systems there very few number of users. In New York, 12 calls only simultaneously supported over 1000 square mile area.

In 1968, Bell laboratories demonstrated the concept of cellular system. In the cellular concept contains 2-way communication. This type of communication used hexagonal , N-cell frequency reuse pattern by using the intracellular mobile stations (MS), which are controlled by a base station (BS). The factors which improve the capacity of cellular system are handoff, frequency reuse and sectorization . By decreasing the power of BS in the cell, in another BS the particular frequency can be reused which is remotely far away. Handoff between stations intensively increases the flexibility provided to the customer. This in turn improves the capacity and user access area is also expanded.

signal processing technology and very large scale integration (VLSI) were developed in 1980s, which paved the route for the digital era. In this generation digital signal processor are used for the 2G cellular. ASICs are used, which reduced the size of mobile phones and new signal processing features. Second generation systems are of digital nature, which offered elementary data services and improved voice quality compared to that of previous generation. 2G systems were designed for the improvement of communication. In 1G radio signals are analog where as in 2G systems radio signals are digital.

2G systems are mainly developed into the CDMA and TDMA systems based on the type of multiplexing is used. in less popular areas digital signals are not reaching the tower. In digital signal call completely fails to connect when the signal strength is less, where as in analog systems it used to gradually drop.

3G is the generation of mobile phones and telecommunications. In 3G different countries used different types of radio interfaces. Mainly used radio interface is W-CDMA, FDMA is also used in this generation. 3G has various application such as mobile tv, video demand, video conferencing etc. In this generation the users increased enormously, the demand for channels also increased. The main impact on the system capacity and quality of service provided by the service provider. Researches where conducted to increase the system capacity and to decrease the call failing during the handoff.

The main issue of the mobile system is the design. Radio spectrum is limited, which must be shared by several users. Each is cell is allocated with the portion of the total frequency of the spectrum. Users in the particular cell can use the channel allocated to that cell. Different cells can use the same channel separated by the minimum distance between the cells because to reduce the co-channel interference. There are three types of channel allocation techniques, they are fixed channel allocation, dynamic channel allocation, hybrid channel allocation.

1. BACKGROUNDS:

In cellular systems, the number of mobile systems under a base station is random and time varying. The users of mobile systems move between cells, so there will be variations in the number of users under the particular base station. So there are lots of variations which causes the traffic and handoff of mobile systems. In the third generation mobile communication systems there is lot of research work is carrying. The objective of the research is to offer personalized and integrated services for the mobile users with the service quality than that of fixed users. In the third generation there is lot of demand for the personal communication, there is explosive growth of the user community because its available for affordable price. Increase in the mobile customers and the need of diversity will be a great challenge to utilize the bandwidth. The radio spectrum is limited it should be carefully planned for the usage.

The research work on radio channel allocation mainly focuses on the admission capability and connection continuity. It gives out the compressed channel exploitation , which in turn maximizes the number of channels. If there is any special variation in requirement of the service, full admission capacity can’t be achieved by fixed channel allocation [1]. We are considering the dynamic channel allocation (DCA)[2]due to this service request imbalance. In DCA, channels are allocated according to the service requests distribution and load sharing also improve the user admission capacity.

1.1 PROBLEM DESCRIPTION:

The initial connection requests to start new calls are considered to improve the user accommodation capability. Accommodation capacity is based upon the admission capability of new user. Since the user moves around, its needed to establish the connection many number of times with in a single call duration. The user accommodation capacity also depends upon the connection continuity. Impulsive call break takes place when a cellular mobile user transfers from its serving cell into a new one [8], but it is not sure that channel is assigned in the different cell to remain in connection. Protecting the connection continuity is studied extensively. The basic techniques which are used to establish connection continuity for mobile users include guard channel[3], predictive channel reservation and handoff queuing. The other techniques of handoff protection are subrating, channel sharing and channel carrying [4].

Handoff protection strategy acquire pessimistic effect on the new user admission. The intake of new users in to the system are reduced by the priority based handoff protection schemes such as guard channel, handoff queuing, and predictive channel reservation. particular portion of the available channels are confined to only the new users by the Guard channel , so guard channel elimination on the new user admission is apparent. Smaller impact on the new user admission is the advantage of handoff queuing over the guard channel. Assume, both handoff queuing and guard channel techniques contains the equal number of nominal channels, the over lapping cell structure infatuated by handoff queuing, which leads to the higher channel density than guard channel. So the minimum impact of the channel queuing can be attributed to the increase number of nominal channels. To differentiate these techniques, let us observe the case which is similar channel set is deployed to envelop the same service area with implementation of the two strategies respectively. The cell Overlapping layout demands a huge amount of the reuse factor in order to continue the co-channel interference distance, compared to that of guard channel strategy only fewer nominal channels per cell present in the handoff queuing strategy, since the other technique does not need the cell overlapping structure. Both the number of guard channels and non-guard channels may be equal. Equal level of handoff protection can be achieved by substituting guarded channels for handoff queuing. Due to exchange problems in handoff queuing , new call admission capability and handoff protection cont be realized. though reservation channels are not properly used, new users are blocked by the predictive channel reservation.

New user admission capability consists of some disadvantages because of handoff protection. In order to over come these constrains researches investigated chances for better providing handoff protection. In [5] Oh and Tcha introduced the division of nominal channels to protect and unprotect channel sets in order to minimize the handoff failure. Therefore a predefined grade of service satisfies the expected results for the above proposed division of nominal channels. The functioning of handoff protection and new user admission is affected due to adding or removing the guard channels. If the handoff requests are less then the new users access guard channel because of dynamic channel allocation[7].

2. Current status and development of research:

2.1 Literature survey:

If an user being engaged in a call connection, then he said to be active. The number of factors influence the active time that include walking or driving, speed, impediment and delay at street intersections, traffic density around, shopping intensions and so on. For this dwelling time negative exponential function is good approximation to the probability distribution through the assumption of various factors. when an active mobile user found to be approaching cell boundary, then the Channel reservation for handoff is conducted. The speed and position of active mobile user are monitored to calculate the remaining time left connection with the particular current cell. If the remaining time falls below threshold is known as channel reservation interval ( CRI). After confirming the the intention of transfer of the call to the new cell, target cell receives the request for the channel reservation. if there is any ideal channel in the target cell then it is reserved and it is known as locked which means temporarily it cont be used by any other. If in the target cell does not contain any free channels then the reservation request will be in a queue. After channel is emptied in the target cell, the request queue searches to find any requests which are to be processed. The request leaves the queue by assigning it to the free channel.

A released channel remains to be free until next channel requests for it when an queue is empty. After sending the reservation request the mobile user can end this current call connection. In this situation the target cell receives reservation cancellation request from the user. After receiving a cancellation request the locked channel will be released by the the target cell after processing corresponding reservation request. We assume CRI to be accurate enough that call completion is the single account for a mobile user not to show up at ending of the CRI. If channel has been reserved to take it over or blocked for mobile user, then the target cell handoff will be successful. Whereas in the previous cases the mobile user continues its call on the new channel until leaving or call completion while in the later on into termination [8], since new call is not prioritized, if a free channel exists then new user will be accepted or else it is blocked and cleared from the system. The following figure describes the working process of reservation admission in the flowchart.

Markov Approach

A markov model is implemented for analysis of the some of active channels and the number of reservation requests which are to be processed. Consider for each cell C number of channels are allocated and buffer size limit for requesting queue is S. The transition rates of the neighbouring channels are obtained as follows. Before channel reduction new calls and handoff calls are entertained, consider the gross arrival rate as the transition rate. When a handoff call reserves one channel for later use, immediately new call takes one channel for the later use. Whenever all channels have been occupied new call is rejected and reservation request is queued upto maximum length of S, which in result get a transition rate equal to the arrival rate of the channel reservation requests only.

Reservation of a channel extends the channel holding time from channel utilization interval(CUI) to channel occupation interval (COI). COI is also assumed that it is exponentially distributed, the mean value of which is obtained by[8]

The expected value of the inactive period of a reserved channel before the utilization of channel is known as the dormant period, dormant period is stated dependent that longer dormancy can be expected and written as

[8]

The average dormant time on state n is given as

[8]

Let Fx(t) is considered as the cpd (Cumulative probability distribution ) of the time interval before the ( X + 1)th channel release. The Fx(t) can be written as

Fx(t) [8]

We canapproximate the sojurn of a request in the queue, which has to be exponentially distributed to give out a time independent request. The living rate that has the value equal to 1/Tcri. The state probabilities are given by

2.2 EVALUVATION:
Traffic model supports assures mobility properties and certain geometry in real-world cell plan.
Where as manhattan model considers a classic city scenario which is regarded as by the association of buildings, big structures with streets.
In the manhattan model the connection distracts, when a mobile user roams in the streets, a street corner and suffers a sharp signal strength path loss.
Handoff protection with prudent channel usage decreases the user accommodation capacity.
In the markov approach, accommodation capacity is evaluvated by using the single over the entire system.
2.3 OUTLOOK:

In this paper, we have discussed the impact of on capacity of the cellular mobile systems by the channel reservation. A user should receive un disrupted service through out the life time after admission which is known as capacity. By using the handoff protection, capability of new user admission increases to that of connection continuity. user accommodation capacity is weakened by handoff protection. Which indicates system capacity and service quality are conflicting objectives. So tradeoff is cont be eliminated. Our further research to be carried out on channel reservation with out degrading the system capacity

REFERENCES:

[1] S.Jordan and A.Khan, “A Performance bound on dynamic channel allocation in cellular systems: equal load”.

[2] D.Everitt and N. MacFayden, “analysis of multicellular mobile radio telephone systems with loss.”

[3] K. Yeung and T.S. Yum, “Compact pattern based dynamic channel assignment for cellular mobile systems.”

[4] “channel carrying: A novel handoff scheme for mobile cellular networks.”

[5] S. H. Oh and D. W. Tcha, “prioritized channel assignment in a cellular radio network.”

[6] F. A. Cruz-Perez, D. Lara-Rodriguez and M. Lara “ fractional channel reservation in mobile communication systems.”

[7] Y. C. Kim, D. E. Lee, B. J. Lee, Y. S. Kim, and B. Mukherjee, “Dynamic channel reservation based on mobility in wireless ATM networks.”

[8] Yi Xu, Quan Long Ding, Chi Chung Ko, “impact of handoff protection strategies on cellular mobile system capacity.”

The quality of broadcasting is changing by the appearance of the services which fuses broadcasting communication technologies. Different standard has been developed for this purpose to improve the quality of service. The aim of my investigation is to find out the development path of the digital broadcasting standard in Europe, USA and Japan. In this paper I also outline the operation of each standard and present their comparison based on their services and technical parameter.

Introduction

Digital broadcasting set to transform the communication landscape now a day. The digital switchover will leapfrog existing technologies to connect the uncorrected in underserved remote communities and close the digital divide. The goal of this achievement is to bring structural development of digital terrestrial broadcasting and sufficient flexibilities for adoption to the changing telecommunication environment. The switchover will create new distribution network and expand the potential and multimedia data making application and services. The digital dividend accruing from efficient in spectrum usage will allow more channels to be carried across fewer airwaves and lead to greater convergence of services. The digital broadcasting will support mobile video internet and multimedia data making application, services and information accessible and usable anywhere and at any time. Its inherent flexibility opens the door for new technology such as high-definition television and handheld TV broadcasting.

Standard

The digital television standard describes a system designed to transmit signal by means of digital modulation technique. Moreover it permit’s a level of quality and flexibility and enable a significant step up performance, services. The level of standardization of the DVB is quite advanced, and relevant recent international standards and related documents are introduced and referred to for easy access to the agenda seeking technical details. Each standard proposed and established by the regional consortium, research centre and Telecommunication Company according the local broadcasting consumer needs, demand and different parameter.There are several digital TV standards developed and deployed in different countries:

• ATSC standard for US.
• ISDB-T in JAPAN.
• DVB-T in Europe.

In early 1990 European broadcaster, equipment manufacturer and regulatory agencies have managed to develop a standard for digital TV for this region. A memorandum of understand has been launched by the stake holder and was signed September 1993. The mission of this group is to protect inter operable standards for the global delivery of digital media service. The DVB-T standard has been designed for stationary and portable terrestrial reception with multi path fading. It uses OFDM with guard interval because it uses large number of carrier per channel modulated in parallel via an FFT process. There are two transmission modes; the first one is 8k mode which requires smaller symbol length and 8192-point FFT. It is suitable and design for single frequency network (SFN).

An SFN is a network where a number of transmitters operate on the same RF frequency. An SFN can cover a country and offer better utilization of the available spectrum. DVB -T SFN Network Architecture The second mode is called 2K mode which use 2048-point FFT. It can be use for single transmitter operation and small SFN with limited distance between two transmitters. The guard interval is 25% of the total symbol length but shorter guard interval is also possible. The total bandwidth for the terrestrial 8MHz TV channels is 7. 6MHz but the system parameters can be scaled for 6/7 MHz TV channels.

The bit rate for the 8MHz is 4. 98Mbits/s to 31. 7 Mbits/s but this range is depends on channel choosing, coding parameters, modulation techniques and guard interval duration. DVB-T use coherent modulation. Different signal constellations need to be considered between QPSK and 64-QAM. In the receive side estimated channel amplitude and phase are required and use 10% of the total bandwidth.

It also has the capacity of using hierarchical modulation technique where two completely separate data stream are modulated onto a single DVB-T signal. A high priority stream is embedded within a low priority stream.As a result the broadcaster can target two different types of receiver with two different services. “For example, DVB-H mobile TV services optimized for more difficult reception conditions could be placed in the HP stream, with HDTV services targeted to fixed antennas delivered in the LP stream. ” Terrestrial DVB-T implement coded orthogonal frequency division multiplexing (OFDM) because of its tolerance to multipath. It provide data payload up to 19Mbps which allow transmitting one HDTV program and up to 4SD program. The channel coding is based on convolution code and the range of code rates are 2/3, 5/6, 7/8.

In DVB-T system the data and transmission level separated in order to ignore unequal error protection (UEP). For video coding where low bit error rates are required use outer Reed-Solomon (RS) code where a block of 188 byte data is coded into block of 204 byte data. The error which is produced by the decoder has eliminated by inserting short byte interleaver between the outer RS code and inner convolutional code.DVB-T2 is a new transmission standard which is the upgraded version of DVB-T. It offers 30% increase in multiplexing capacity then the DVB-T standard. ATSC (Advanced Television Systems Committee)In the USA the broadcasting environment is considerably different from the rest of the world. The technical parameter of the station resulting in different coverage area and quality of audio or video service appear to be important economic factor that are the vital to the broadcaster in which many of them think it has to be preserved in the transition to the digital system.

After a decade of intense research and development by the Advanced Television System Committee and a consortium of electronics and telecommunications companies has develop a standard for this region which is ATSE standard.In early 1990 ATSE standard was developed and offer high quality of video and audio transmission and ancillary data over single 6MHz terrestrial television broadcast channel.This standard use single carrier modulation scheme and adopted eight level vestigial sideband amplitude modulation technique. In this technique the data are encoded by varying the amplitude of a single carrier frequency. Portions of one of the redundant sidebands are removed to form a vestigial sideband signal. A significant advantage of 8VSB for broadcasters is that it requires much less power to cover an area. VSB is also more resistant to impulse noise.

Some stations can cover the same area while transmitting at an effective radiated power of approximately 25% of analog broadcast power. In ATSE system Multiple MPEG programs are combined then sent to a transmitting antenna. In the US broadcast digital TV system, an ATSC receiver then decodes the TS and displays it on a TV.

This standard can reliably deliver 19. 4 Mbits/s of data throughput in a single channel and 38. Mbits/s in 6MHz cable television channel. This means encoding HD video essence at 1. 106 Gb/s (highest rate progressive input) or 1. 244 Gb/s (highest rate interlaced input) requires bit rate reduction by a factor of 60.

ATSC use compression technology to achieve the bit rate reduction. It uses minimum bits of video, audio and data for the compression to optimize the scarce resource of the transmission channel. During the compression scheme it also preserves the level of quality of the application. ATSC System ATSC have two modes of operation. One is 8-VSB simulcast terrestrial mode and the other is 16-VSB high data rate mode. It use huge data ‘pipeline’ to support a wide Varity of application. In a 6Hz channel a broadcaster can transmit HD program or an HDTV program with one or more simultaneous standard definition program or multiple simultaneous SDTV program or a virtually limitless array of data service or various combination of all three.

ISDB-T System in Japan NHK Science and Technical Research Lab in Japan have proposed the concept of ISDB standard.From this approach a system was created and configured for the terrestrial broadcasting. The most important aims were to establish this terrestrial system to achieve frequency efficient coverage and flexibility by using Single Frequency Network (SFN), portable and mobile receiver with rugged reception. To establish this concept a variant of OFDM was developed in order to build Band Segment Transmission (BST) OFDM. In BST-OFDM each signal consists of frequency block with bandwidth of 571500 or 428 KHz corresponding to 1/14 of the terrestrial television channel spacing. It could be 6, 7 or 8 depending on region. It uses different carrier modulation scheme and coding rates of the inner code on the different BST-Segment for its hierarchical transmission.

ISDB-T use UHE 470MHz to 77MHz and has 6MHz width fifty two channel. Each channel are the combination of 13 segment. The TV station uses the combination of the segment for broadcasting the TV program. For example they combine one 12segment for HDTV program, one 8segment for MDTV and three 4segment use for SDTV program. seg use single segment for mobile terrestrial digital audio/video broadcasting services.

The transport stream used for 1seg is MPEG-4AVC. Each case the basic modulation and coding modes of segment are QPSK, DQPSK, 16QAM and 64QAM and codes rates between 1/2 and 7/8 are available. Time interleaving technique has been implementing for enhancing reception performance in the noisy, mobile indoor environment. It also use Emergency Warning System (EWS) feature to warn the population in emergencies.ISDB-T can transmit one HDTV and up to 4 SDTV by using MPEG-2 transporting stream while the transport stream used for 1seg is MPEG-4 AVC.

Comparison

Each standard have their unique features, techniques and performance depending upon the geographical infrastructure, consumer demand. Therefore, countries and its administrations does the intense research before deploy them. The selection mainly based on modulation technique, the use of spectrum resources, coverage requirement, transmission network structure, reception condition, type of service required, cost to the consumers and broadcasters. After my investigation I tried to establish a comparable analysis by considering different impairments and operational conditions. Comparison from the service aspect The following table 1 shows the summary of the performances of 3 DTTB system standards from their service aspect: The SFN operation uses a cluster of transmitter in DVB-T and ISBD-T to cover a designated service area and provide strong field strength throughout the core coverage area. ATSC system does not design to support SFN operation, because ATSC Standard has adopted single carrier system.

Note:

• For ATSC and DTV-T, actual commercial service is not popular.
• For DVB-T, SDTV mobile reception is possible.

In the case of DVB-T, another frequency required for portable reception service.

The summary comparison of the three standard

After all discussion I can summarize the comparison of the three standard the following way. Summary of 3 DTTB systems comparison:

1. Under the static multipath condition, DVB-T and ISDB-T are almost same, but under the dynamic multipath condition ISDB-T is superior than DVB-T because ISDB-T support the time interleave.
2. DVB-T has a offered hierarchical transmission function (non-uniform transmission), but it has no practical service in the world because of it degrade performance of the receiving side.

Conclusion

The merits of the digital TV standard has been recognized in worldwide because of its offer like more TV channels, better images and improved sound quality. These broadcasting standards also allow new possibilities like pay TV, video-on-demand and interactive contents. But neither of these technologies will appear as conquering over the other, and neither will be forced to accept a role as the failure in the records of broadcasting history.In fact, all these standards can and likely playing equally important roles in the terrestrial TV broadcasting industry. Therefore, the choice will be based on how those digital TV standards meet the particular requirements or priorities of each country as well as the nontechnical factors such as geographical, economical and political condition of the country need to be considered. The broadcasting industry is going through a massive technical up gradation phase. This phase brings many open door opportunities for various players across the value chain of digital broadcasting.

Proper government policies and regulation are essential to protect unlawful abuser. Decisions by the government, companies, competitors and consumer are playing critical roles in the development and promoting of digital terrestrial television technology.

References

1. Diego Villa, “Digital TV Standard: DVB-T, ATSC, ISDB-T,” Your Electronic Open Source, Nov 26th, 2008[online]. Available: http://dev.emcelettronica. com/digital-tv-standards-dvb-t-atsc-isdb-t. [Accessed: Dec 2nd, 2009]
2. W. Hoeg and T. Lauterbach, Digital Audio Broadcasting principles and applications of Digital Radio, second Edition. England: John Wiley, 2003
3. Y. Wu, E. Pliszka, B. Caron, P. Bouchard, and G. Chouinard, “Comparison of Terrestrial DTV Transmission System: The ATSC 8-VSB, the DVB-T COFDM, and the ISDB-T BST-OFDM,” IEEE TRANSACTION ON BROADCASTING, VOL. 46, NO. 2, JUNE 2000.
4. http://en. wikipedia. org/wiki/ATSC_(standards)