机构地区: 中山大学信息科学与技术学院
出 处: 《通信学报》 2005年第8期113-116,121,共5页
摘 要: 为进一步提高OFDM的传输速率,提出了正交波束空间分集—OFDM方法。利用智能天线的数字波束形成(DBF)技术,首先在时域构造出多个正交空分信道,然后对每个空分信道进行OFDM解调,最后根据选择性分集算法获得频域序列。理论分析和仿真结果都表明,至少有一个空分信道的频响特性优于全向信道的频响特性,并且各正交空分信道频响特性间的相关性很低,因而分集合成信道的频响特性明显优于全向信道、每个空分信道的频响特性。与单天线OFDM系统相比,正交波束空间分集—OFDM方法能够实现更高的传输速率。 In order to increase the data rate of OFDM further, the orthogonal-beams space diversity-OFDM method was proposed. Firstly, employing the digital beamforming (DBF) technique of smart antennas, multiple orthogonal space-divided channels in time-domain were created, then performed OFDM demodulations for all space-divided channels, finally, obtained the frequency-domain's sequence according to the selection diversity algorithm. Both theoretical analyses and simulating results indicate that: At least there was one space-divided channel whose frequency response is superior to the isotropic-antenna channel's, furthermore, the cross-correlation between every two orthogonal space-divided channel's frequency responses was very weak, hence the frequency response of the diversity-constructed channel was obviously superior to both frequency responses of an isotropic-antenna channel and each space-divided channel. Comparing with the single antenna OFDM system, the orthogonal-beams space diversity-OFDM method can implement a higher date rate.
关 键 词: 通信与信息系统 正交波束空间分集 数字波束形成算法 频率选择性衰落信道 智能天线 数字波束形成 系统 空间分集 正交 移动通信