Towards Real-Time CMA Equalization by using FFT for Signal Blocks transmitted over an Aeronautical channel
Advisor
Cole-Rhodes, ArleneMoazzami, Farzad
Affiliation
Morgan State University, Dept Elect and Comp EngIssue Date
2016-11Keywords
Blind EqualizationConstant Modulus Algorithm
Alphabet Matched Algorithm
FFT
Channel Estimation
SOQPSK
iNET
Aeronautic channels
MMSE
Equalizers
Metadata
Show full item recordRights
Copyright © held by the author; distribution rights International Foundation for TelemeteringCollection Information
Proceedings from the International Telemetering Conference are made available by the International Foundation for Telemetering and the University of Arizona Libraries. Visit http://www.telemetry.org/index.php/contact-us if you have questions about items in this collection.Abstract
We consider the problem of equalizing data blocks of signals, which have been transmitted over an aeronautical channel using two different modulation schemes. The equalization is performed using the block-processing constant modulus algorithm (CMA), and in order to achieve real-time processing a Fast Fourier Transform (FFT) is used to compute the gradient of this cost function during equalization. The equalizer length is chosen to be five times of the channel length. For the first experiment, we present the result of equalizing a set of measured data, which was modulated and transmitted using the iNET packet structure with SOQPSK modulation. In this case, the CMA equalizer is first initialized using MMSE and the equalizer coefficients are then updated once, using each entire block (iNET packet). In the second experiment, we apply the FFT-based block processing equalizer to received data blocks of QPSK signals, which have been randomly generated and transmitted over an aeronautical channel. A modified constant modulus algorithm and alphabet matched algorithm (CMA + AMA) equalizer is used to recover these data blocks. For this case of QPSK signals, the equalizer performance is evaluated over 500 Monte Carlo runs, using the average symbol error rate (SER).Sponsors
International Foundation for TelemeteringISSN
0884-51230074-9079