This paper is devoted to present a multi-channel, high resolution, fast lock phase locked loop (PLL) for surveillance radar applications under influence of system noise. Phase detector based PLLs are simple to design, suffer no systematic phase error, and can run at the highest speed. Reducing loop gain can proportionally improve jitter performance, but also reduces locking time and pull-in range. The system is studied under influence of system noise in the range from 5 to 30 dB to reflect the reliability of the system under these conditions. The results perform a comparison of noise power, VCO control input, Lock time, ISE and ITSE Performance indices for three selective channels among 38 channels operated in the desired frequency range. The results show superiority of the system in difficult operating conditions.