基于Taylor級(jí)數(shù)近似補(bǔ)償?shù)母倪M(jìn)數(shù)控振蕩器實(shí)現(xiàn)
基于本文設(shè)計(jì)結(jié)構(gòu)的改進(jìn)數(shù)控振蕩器采用了Verilog HDL進(jìn)行實(shí)現(xiàn),并在Altera公司CycloneⅡ系列的FPGA上進(jìn)行了綜合、布局布線和驗(yàn)證,本設(shè)計(jì)也在國(guó)家“863”項(xiàng)目“軟硬件可重構(gòu)的新一代無(wú)線通信統(tǒng)一平臺(tái)研究”中得到應(yīng)用,在速度和精度上都能很好的滿足平臺(tái)的需要。
結(jié)語(yǔ)
本文提出一種適用于軟件無(wú)線電通信系統(tǒng)的數(shù)控振蕩器實(shí)現(xiàn)新方法,該方法利用流水線CORDIC結(jié)構(gòu)來(lái)實(shí)現(xiàn)數(shù)控振蕩器,這樣可以實(shí)現(xiàn)高速的數(shù)控振蕩器;同時(shí),該方法采用殘余相角補(bǔ)償、二階泰勒(Taylor)級(jí)數(shù)近似、相位抖動(dòng)等措施來(lái)補(bǔ)償CORDIC在精度方面的不足,使數(shù)控振蕩器的SFDR值得到了很大的提高。該方法實(shí)現(xiàn)的數(shù)控振蕩器能滿足軟件無(wú)線通信系統(tǒng)的速度和精度的要求,并且也成功應(yīng)用在軟件無(wú)線電平臺(tái)上,表現(xiàn)出很好的性能。
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