Delta modulation for channel feedback in transmit diversity systems

In a wireless communication system with multiple transmit antennas, knowledge of the channel at the transmitter can be used to increase link and system capacity. In a frequency division duplex system, the channel may be estimated by the receiver and communicated back to the transmitter for use in future transmissions. Efficient schemes that achieve channel feedback in this manner are of interest. We present a channel feedback scheme that uses delta modulation to encode channel information efficiently by exploiting the temporal correlation of the wireless channel. A system with multiple transmit antennas and a single receive antenna is used to evaluate the performance of the channel feedback scheme. The effect of feedback channel errors on system performance is shown. The presented method is found to be advantageous for channels with low to moderate Doppler frequencies.

[1]  Mikael Skoglund,et al.  On the capacity of a multiple-antenna communication link with channel side information , 2003, IEEE J. Sel. Areas Commun..

[2]  James R. Zeidler,et al.  A simple gradient sign algorithm for transmit antenna weight adaptation with feedback , 2003, IEEE Trans. Signal Process..

[3]  Gregory W. Wornell,et al.  Efficient use of side information in multiple-antenna data transmission over fading channels , 1998, IEEE J. Sel. Areas Commun..

[4]  Elza Erkip,et al.  On beamforming with finite rate feedback in multiple-antenna systems , 2003, IEEE Trans. Inf. Theory.

[5]  Srinath Hosur,et al.  Performance analysis of closed-loop transmit diversity in the presence of feedback delay , 2001, IEEE Trans. Commun..

[6]  Peter No,et al.  Digital Coding of Waveforms , 1986 .

[7]  K. H. Barratt.  Digital Coding of Waveforms , 1985 .

[8]  Srikrishna Bhashyam,et al.  Feedback gain in multiple antenna systems , 2002, IEEE Trans. Commun..

[9]  Upamanyu Madhow,et al.  Space-Time transmit precoding with imperfect feedback , 2001, IEEE Trans. Inf. Theory.

[10]  Kambiz C. Zangi,et al.  Capacity-achieving transmitter and receiver pairs for dispersive MISO channels , 2003, IEEE Trans. Wirel. Commun..

[11]  A. Paulraj,et al.  A simple scheme for transmit diversity using partial channel feedback , 1998, Conference Record of Thirty-Second Asilomar Conference on Signals, Systems and Computers (Cat. No.98CH36284).

[12]  Kwang Bok Lee,et al.  Efficient weight vector representation for closed-loop transmit diversity , 2004, IEEE Trans. Commun..

[13]  Gregory E. Bottomley,et al.  Rake receiver finger placement for realistic channels , 2004, 2004 IEEE Wireless Communications and Networking Conference (IEEE Cat. No.04TH8733).