Two-way satellite relaying
We have discussed the problems associated with the TWSR in this chapter. A training protocol for the TWSR system has been discussed and studied in detail. This training protocol is used to estimate the CSI required for self-interference cancellation and symbol decoding with sufficiently low estimation noise. Performance of this training-based scheme has been analysed in terms of BER and average capacity. Then, differential modulation-based TWSR has been discussed. The use of differential modulation allows for obtaining a differential detector which does not require any channel information in the destination ES. This useful virtue of the proposed differential detector allows for avoiding the difficulty of channel estimation in two-way AF satellite communication. Further, two beamforming and combining schemes for TWSR have been discussed in this chapter. In first scheme, the calculation of beamforming and combining vectors has been performed by utilizing local channels of ESs, whereas second scheme is SNR optimal and the beamforming and combining vectors have been calculated by using maximum eigenvalue criterion. It can be concluded that SNR optimal beamforming and combining outperforms the local channel-based beamforming and combining scheme. All the presented schemes are very useful for practical implementation of TWSR communication systems.
Two-way satellite relaying, Page 1 of 2
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