采用OFDM-LFM的MIMO雷达高速目标波形设计

MIMO radar waveform design via OFDM-LFM for a high speed target

单基地多输入多输出雷达由于其宽发射波束的特性而能有效解决目标高速运动跨越发射波束带来的能量损失问题;但是现有波形对速度容忍性较差,高速目标回波匹配滤波能量损失较大.因此,有必要研究适用于高速目标背景下的多输入多输出雷达波形.文中提出了一种基于正交频分复用线性调频信号的多输入多输出波形.该波形不同发射通道分时复用一组不同频段的线性调频信号,从而得到带宽相同的可分离多路多输入多输出雷达波形.仿真结果表明,文中设计的多输入多输出雷达波形能有效降低高速目标回波匹配滤波的能量损失,适用于高速目标背景.

By ap plying the wide tra nsmi t beam prope r ty, colocated multi-input and multi-output （MIMO ）radar can save the energy loss caused by the transmit beam crossing effect of a high speed target. However, existing MIMO radar waveforms have a bad velocity tolerance ability. When the echo of the high speed target is match filtered with these waveforms, the energy loss is unncglcctablc. Therefore, it is necessary to design a suitable MIMO radar waveform under the high speed target condit ion. This paper derives thewaveform based on the orthogonal frequency division mul tiplexing linear frequency modulation （OFDM- LFM） signal. A linear frequency modulation（ LFM） signal set with frequcncydivcrsity is time divisionmultiplex used by different channels. Hence, all waveforms are separable and share the same bandwidth. Simulat ion resul ts show that the proposed M IMO ra d a r waveform can effectively reduce th ethe matched filtering process, which fits the high speed target background.