1. EDGE TECHNOLOGY

2. INTRODUCTION EDGE is a digital mobile phone technology that allowsimproved data transmission rates as a backward-compatibleextension of GSM. EDGE/EGPRS is implemented as a enhancement for2.5G GSM/GPRS networks, making it easier forexisting GSM carriers to upgrade to it. EDGE doesnt requires much hardware or softwarechanges to be made in GSM core networks. 3. TRANSMISSION TECHNIQUES In addition to GMSK, EDGE uses 8-PSK for the upperfive of its nine modulation and coding schemes. Triples the data rate offered by GSM. 4. GMSK Gaussian Minimum Shift Keying, GMSK, the form ofmodulation with no phase discontinuities used toprovide data transmission with efficient spectrum usage. GMSK has high spectral efficiency, but it needs a higherpower level than QPSK, for instance, in order to reliablytransmit the same amount of data. It has advantages of being able to carry digitalmodulation while still using the spectrum efficiently. 5. Waveforms and PSD 6. GMSK Modulation 7. 8-PSK 8-PSK is usually the highest order PSK constellationdeployed. There are 8 different phase changes defined, each phasechange represents the transmission of 3 bits. Baud rate is 1/3rd of bit rate for 8-PSK system. 8. Constellation Diagram 9. Waveforms of PSK 10. Transmitter Block DiagramSerial toparallelconverter Sine wavegeneratorphasecontrolledby VAb(t)Digital toanalogDigitalinputconverter M-ary PSKoutputAnalog voltageVAN bit symbol012N-1 11. Advantages of 8-PSK Bandwidth reduces as no. of bits/symbol increases. It gives better performance where the signalamplitude varies due to the characteristics of thetransmission medium. 12. Disadvantages of 8-PSK Probability of error increases as no. of bits/symbolincreases. Transmitter and receiver are very complex. 13. EDGE MODULATION AND CODING SCHEMEThe channel encoding process in GPRS as well asEGPRS/EDGE consists of two steps:1. first, a cyclic code is used to add parity bits, which arealso referred to as the Block Check Sequence,2. followed by coding with a possibly puncturedConvolutional code. 14. CYCLIC BLOCK CODES A linear (n, k) code is called a Cyclic code if allcyclic shifts of a codeword are also a codeword.U ( u , u , u ,..., u)i cyclic shifts of U( , ,..., , , , ,..., )1 1 0 1 2 1( )0 1 2 1 n i n i n n iinu u u u u u uUExample:U(1101)(1) (2) (3) (4) (1110) (0111) (1011) (1101)U U U U U 15. BLOCK DIAGRAM : CONVOLUTIONAL CODINGInformationsourceRate 1/nConv. encoderModulator1 2 ( , ,..., ,...) i m m m mInformationsinkRate 1/nU G(m)U U U UU u ,...,u ,...,uConv. decoder( , , ,..., ,...)1 2 3iCodeword sequencei i ji ninDemodulatorInput sequence1Branch word ( coded bits) ( , ,..., ,...) 1 2 i m m m mZ Z Z Z( , , ,..., ,...)1 2 3Z 1outputs per Branch wordDemodulator outputsfor Branch wordreceived sequenceni ji niiiiZ z ,...,z ,...,zChannel 16. CODING SCHEMES 17. POPULATION COVERAGE BY TECHNOLOGY 18. MAXIMUM DOWNLOAD AND UPLOAD SPEED EDGE can carry a bandwidth up to 236 kbit/s for 4timeslots. It provides data rates in the order of 200 kbit/s. 19. EDGE SPECIFICATIONS 20. ADVANTAGES It only requires program upgrade of some networkelements. EDGE can transmit and receive data three times as fastas a normal GPRS connection. 90% of the existing operators using the GSM networksprovide internet access through EDGE. 21. DISADVANTAGES The hardware part of MS is to be replaced. It consumes much of the battery power. 22. APPLICATIONS Mobile Internet access Wireless access to databases Electronic banking Electronic payment Messaging Security/supervisory systems Reservation system (e.g. hotel, theater, flights) Video telephony Telescoping 23. REFERENCES Wireless Communications & NetworkingBy Vijay Garg, Morgan Kaufmann Publication, 2009 Edition M. Kottkamp, EDGE Evolution, 2008 Articles- EDGE, Phase Shift Keying, Convolutional Code by Wikipedia GMSK- radio-electronics.com 24. THANK YOU