|
|
|
| Impact of Non-ideal SNR Estimation on the Performance of BICM-ID Systems |
| Nie Yuan-fei;Ge Jian-hua; Wang Yong |
| National Key Lab. of Integrated Service Networks, Xidian Univ., Xi'an 710071, China |
|
|
|
|
Abstract This paper proposes an intuitive modeling of a prior information with Signal-to-Noise-Ratio (SNR) mismatch for Bit-Interleaved Coded Modulation with Iterative Decoding (BICM-ID) systems. The extrinsic information transfer chart is applied to analyze the impact on BICM-ID caused by non-ideal SNR estimation for different constellations, labeling methods and channel types. It is found that the results are semblable for these cases. The performance of BICM-ID systems with different frame length is compared with SNR mismatch varied. The system performance decreases acutely when SNR mismatch is smaller than -3dB and maintains when it is bigger than 0dB for long frame, while it is more sensitive for SNR underestimation than overestimation for moderate and short frames. Besides these, SNR estimation methods are presented for 8PSK in Gaussian channel and 16QAM in Gaussian and Rayleigh channels. Finally, simulation results show these methods are effective.
|
|
Received: 17 August 2006
|
|
|
|
|
|
|
|
|
2008, Vol. 30 
