Improvement on Diversity Gain with Filter Bandwidth Enlargement in Fractional Sampling OFDM Receiver
Improvement on Diversity Gain with Filter Bandwidth Enlargement in Fractional Sampling OFDM Receiver
复制标题
分数采样 OFDM 接收机中滤波器带宽的提高分集增益
DOI：
10.1587/transcom.e93.b.1526
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发表时间：
2010
期刊：
影响因子：
--
通讯作者：
Y. Sanada
中科院分区：
文献类型：
--
作者：
Toshiya Shinkai;H. Nishimura;Y. Sanada
研究了一种基于分数采样的OFDM接收机分集方案。在OFDM系统中，通过FS可以分离多径分量，获得分集增益。发射和接收基带滤波器之间的总频率响应带宽的扩大使FS方案能够实现路径分集。然而，发射滤波器必须根据IEEE802.11a/g等无线标准的频谱掩码进行设计，以避免对其他通信系统的干扰，并且通常将包含发射和接收滤波器的复合信道的频率响应设置为最小带宽，以消除相邻信道信号。为了达到最大的信噪比，通常在发射端和接收端使用相同的滤波器。本文研究了接收滤波器带宽增大所带来的信噪比下降、相邻信道干扰和分集增益之间的权衡问题。计算机仿真的数值结果表明，在一定条件下，为实现信噪比最大化，采用较宽带宽的接收端BER性能优于采用最小带宽的接收端BER性能。
A diversity scheme with Fractional Sampling (FS) in an OFDM receiver has been investigated recently. Through FS, it is possible to separate multipath components and obtain diversity gain in OFDM systems. Enlargement of the bandwidth of the total frequency response between transmit and receive baseband filters allows the FS scheme to achieve path diversity. However, the transmit filter has to be designed according to the spectrum mask of the wireless standards such as IEEE802.11a/g to avoid interference to the other communication systems and the frequency response of the composite channel including the transmit and receive filters has often been set to minimal bandwidth to eliminate adjacent channel signals. In order to achieve the maximum signal-to-noise ratio (SNR), the same filter is commonly used in the transmitter and the receiver. In this paper, the trade-off among the SNR deterioration, adjacent channel interference, and the diversity gain due to the enlargement of the bandwidth of the receive filter is investigated. Numerical results from computer simulations indicate that the BER performance with wider bandwidth in the receiver shows better performance than that with the minimal bandwidth for maximizing the SNR in certain conditions.