This scheme can also adapt ds / dmpsk modulation and demodulation with different base data rate , different pseudo random codes and different intermediate frequency 該方案可以適應(yīng)不同基帶數(shù)據(jù)速率、不同偽隨機碼和不同中頻的ds / dmpsk的調(diào)制和解調(diào)。
This dissertation adopts a universal digital ds / dmpsk modulation and demodulation scheme which is based on fpga . this scheme adopts quadrature balanceable modulation , intermediate frequency sampling , digital matched filtering , delay differential demodulation techniques and so on . it directly processes the digital signals on intermediate frequency without down - conversion , and doesn ’ t need pseudo random codes synchronization and carrier wave extraction circuits 本文采用了一種基于fpga的通用數(shù)字調(diào)制解調(diào)方案,該方案在調(diào)制端采用了正交平衡調(diào)制技術(shù),在解調(diào)端采用了中頻帶通采樣、數(shù)字匹配濾波、延時差分解調(diào)等技術(shù),直接在中頻上進行數(shù)字信號處理,不需要進行下變頻,也不需要增加額外的偽隨機碼同步捕獲和載波提取電路。