Title :
Trans-Modulation in Wireless Relay Networks
Author :
Seddik, Karim G. ; Ibrahim, Ahmed S. ; Liu, K.J.R.
Author_Institution :
Dept. of Electr. & Comput. Eng., Maryland Univ., College Park, MD, USA
fDate :
3/1/2008 12:00:00 AM
Abstract :
In this letter, we consider the trans-modulation design for the decode-and-forward relay networks. We propose to reassign the constellation points at the relay nodes to minimize the symbol error rate (SER) at the destination node. The proposed trans-modulation scheme can significantly improve the system SER performance without increasing the complexity of the system, especially when the relays are close to the source. For this case, improvements of about 2 dB for 16-QAM constellation and about 3 dB for 64-QAM constellation are achieved for the single-relay case.
Keywords :
quadrature amplitude modulation; radio networks; 16-QAM constellation; decode-and-forward relay networks; symbol error rate; transmodulation design; wireless relay networks; AWGN; Automatic repeat request; Bit error rate; Decoding; Error analysis; Euclidean distance; Relays; Transmitters; Transmitting antennas; Wireless application protocol;
Journal_Title :
Communications Letters, IEEE
DOI :
10.1109/LCOMM.2008.071734