International Journal of Applied Engineering Research
ISSN 0973-4562 Volume 10, Number 1 (2015) pp. 1077-1082
© Research India Publications
http://www.ripublication.com
Development of Data Recovery System for the Data
Transmitted over Rayleigh Faded Channel
S. Venkateswarlu
1
, Dr. Sastry JKR
2
1
Research Scholar, Department of ECE, KL University,
Vaddeswaram, 522 502, A.P., India
somu23@kluniversity.in
2
Professor, Department of ECM, KL University,
Vaddeswaram, 522502, A.P., India
sastryjkr2002@yahoo.co.in
Abstract
Wireless communication channel is being used as primary means of
communication nowadays. Data is DPSK modulated and hamming encoded
before being given as input to the Rayleigh Faded Wireless Communication
channel. This paper mainly focuses on the data re-generation techniques from
phase modulated data at the source side. The generated data is made to pass
through the channel by undergoing various transmission impairments. To
accurately regenerate the data at the receiver side equalizers are recommended
for usage. Decision feedback equalizer is one such equalizer that reproduces
the data accurately. It takes care of all types of the noise components and
suppresses the AWGN also. It counters the Doppler Effect and ISI most
accurately.
Key Words: Feedback Equalizer, Doppler correction, I channel and Q
channel.
Data Generation
The input to the system is the message of 'L' number of characters. The model
converts the given text into ASCII code and supplies the bit stream to DPSK
encoder[2].
The general representation for a set of M-ary phase signaling waveform is[5][2]
S(t) = {U(t) exp j ( 2Πf
c
t + 2Π (m-1) / M + θ )}
0 ≤ t ≤ T,
m = 1,2,3,4
θ = initial phase.