నైరూప్య

Low Power LFM Pulse Compression RADAR with Sidelobe suppression

M. Archana, M. Gnana priya

One of the parameters of the pulsed RADAR that contributes range capability is the average power of the transmitter. The average power can be increased by increasing the peak power or transmitted pulse width or both. The complexity in the design of transmitter components to withstand high peak power is the most challenging task. On the other hand larger transmitted pulse width affects the RADAR capability to detect and track lower range targets. Maximum detection range of RADAR is increased by larger pulse width which in turn results in poor range resolution and poor range measurement accuracy. So narrow pulse width is preferred and therefore only the peak power of the transmitter should be increased. Pulse compression is a technique to enhance the average power of the RADAR without compromising range resolution and maximum detectable range. It is a process of transmitting a longer pulse and on receiving compressing it to a shorter pulse. The emphasis of LFM (Linear Frequency Modulation) pulse compression method combines both the benefits of long duration and short duration pulses to enhance range and range resolution of RADAR without increasing the peak transmit power. But the pulse compression of LFM signal with matched filter introduces sidelobes which is objectionable in a way that they may mask smaller targets in vicinity. The solution to this problem is to introduce windowing technique to suppress the side lobes. A simulation was run to compare various windowing techniques (Hamming, Hanning, Blackman, Flattop, Bartlett) in LFM Signal for effective side lobe suppression in low power RADAR.