微电子学
微電子學
미전자학
MICROELECTRONICS
2010年
1期
118-121,135
,共5页
NR解码器%DTMB%CSD%汉明距%SISO
NR解碼器%DTMB%CSD%漢明距%SISO
NR해마기%DTMB%CSD%한명거%SISO
NR decoder%DTMB%Cannoic signed digit%Han Ming distance%Soft-in-soft-out
针对恶劣信道条件下最小汉明距算法判决效果较差的特点,提出了一种改进算法,与4QAM解映射相结合,应用于DTMB系统的NR解码模块.仿真结果表明,改良后的算法令系统性能提高了近1.5 dB;另外,利用NR码字特点,硬件设计中采用对称实现,节约了近一半ROM;定系数乘法器采用CSD编码技术,以节省硬件资源.
針對噁劣信道條件下最小漢明距算法判決效果較差的特點,提齣瞭一種改進算法,與4QAM解映射相結閤,應用于DTMB繫統的NR解碼模塊.倣真結果錶明,改良後的算法令繫統性能提高瞭近1.5 dB;另外,利用NR碼字特點,硬件設計中採用對稱實現,節約瞭近一半ROM;定繫數乘法器採用CSD編碼技術,以節省硬件資源.
침대악렬신도조건하최소한명거산법판결효과교차적특점,제출료일충개진산법,여4QAM해영사상결합,응용우DTMB계통적NR해마모괴.방진결과표명,개량후적산법령계통성능제고료근1.5 dB;령외,이용NR마자특점,경건설계중채용대칭실현,절약료근일반ROM;정계수승법기채용CSD편마기술,이절성경건자원.
As the least Han-Ming distance algorithm does not work well in atrocious channel, a modified arithmetic was proposed, in combination with 4-QAM demapping method, for Nordstrom Robinson (NR) decoder module based on National DTMB Standard. Simulation results indicated that the system performance was improved by about 1.5 dB, compared with the former design. On account of NR code traits, symmetric design was employed, which cut down almost half of ROMs. And CSD code was used for constant coefficient multiplier to save hardware resource.