电讯技术
電訊技術
전신기술
Telecommunication Engineering
2015年
9期
1036-1041
,共6页
跳频通信%π/4-DQPSK差分解调%频差估计%相关峰检测
跳頻通信%π/4-DQPSK差分解調%頻差估計%相關峰檢測
도빈통신%π/4-DQPSK차분해조%빈차고계%상관봉검측
frequency hopping communication%π/4-DQPSK differential demodulation%frequency offset es-timation%correlation peak detection
针对低速π/4-DQPSK差分解调过程中因大频偏导致的性能恶化问题,提出了一种基于相关峰检测的频差估计算法。该算法利用已知发送的M序列对接收信号进行相关检测,根据频偏对同相( I)和正交( Q)两路相关峰值的不同影响进行频偏估计。给出了该算法的理论推导,并将其与传统的Kay估计、Fitz估计、L&R估计进行仿真对比。结果表明,该算法估计范围相当,为符号速率的一半；估计精度略差,信噪比大于0 dB时均方误差优于2×10-4,但显著降低了运算量与实现复杂度,具有很好的工程实用价值。
針對低速π/4-DQPSK差分解調過程中因大頻偏導緻的性能噁化問題,提齣瞭一種基于相關峰檢測的頻差估計算法。該算法利用已知髮送的M序列對接收信號進行相關檢測,根據頻偏對同相( I)和正交( Q)兩路相關峰值的不同影響進行頻偏估計。給齣瞭該算法的理論推導,併將其與傳統的Kay估計、Fitz估計、L&R估計進行倣真對比。結果錶明,該算法估計範圍相噹,為符號速率的一半；估計精度略差,信譟比大于0 dB時均方誤差優于2×10-4,但顯著降低瞭運算量與實現複雜度,具有很好的工程實用價值。
침대저속π/4-DQPSK차분해조과정중인대빈편도치적성능악화문제,제출료일충기우상관봉검측적빈차고계산법。해산법이용이지발송적M서렬대접수신호진행상관검측,근거빈편대동상( I)화정교( Q)량로상관봉치적불동영향진행빈편고계。급출료해산법적이론추도,병장기여전통적Kay고계、Fitz고계、L&R고계진행방진대비。결과표명,해산법고계범위상당,위부호속솔적일반；고계정도략차,신조비대우0 dB시균방오차우우2×10-4,단현저강저료운산량여실현복잡도,구유흔호적공정실용개치。
A frequency offset estimation algorithm based on correlation peak detection is presented to solve the low symbol-rateπ/4-DQPSK differential demodulation performance deterioration due to large frequen-cy offset. This algorithm correlatively detects the received signal using known M sequence and the frequen-cy offset is estimated based on the diffident effect on the correlation peak of inphase( I) channel and quad-rature( Q) channel. Theoretical derivation of the algorithm is given and its capability is simulated and com-pared with Kay estimation,Fitz estimation and L&R estimation. Results show that this algorithm has similar estimation range which is half of symbol rate,slightly poorer estimation precision whose mean-square error ( MSE) is superior than 2 ×10-4 with signal-to-noise ratio( SNR) greater than 0 dB ,but much less calcu-lating amount and implementation complexity. It is more valuable in practical engineering.
