Design and Implementation of Modern X band UP/Down Converter

Modern Active Phased array Radars consist of thousands of transmit receive (T/R) T/R elements, UP-Down converters and digital receivers. In this paper we are going to focus on UP-down converter/RF-IF board, which plays a key role for this active phase array RADAR. Base-band digital signal provides in-phase and quadrature in phase signals which is fed into RF I/Q mixer and consequently upconverted to X band(10-10.5 GHz) and radiated through antenna. However maintaining amplitude and phase of both I-Q across the channel and frequency, imposes lot of challenges particularly in X band for beam steering purpose. Also in a conventional radar receiver errors are introduced due to mismatch between I and Q path, gain/phase mis-match, ADC quantization errors. This paper describes the design and implementation challenges stepwise associated with RF Up-down converter module. State of the art technology has been used for minitiarization of module maintaing temperature and Quality specs. Secondly the multi-channel RF-IF receiver will operates in various modes of operation. The calibration of each receiver will be critical for receive path as well as for transmit path for accurate phase and amplitude control.