A W-band multichannel receiver module for passive millimeter wave imaging

Abstract

A W-band integrated multi-channel receiver for passive Millimeter-wave (PMMW) imaging application is developed. The construction and operating principle of multi-channel receiver module is described. For each channel, heterodyne receiver is realized in order to reach high stability, which is very important to PMMW system. High integration of the multi-channel receiver front end is achieved by using Millimeter-wave integrated circuits (MIMICs) and planar multi-chip module (MCM) design and process. A traveling-wave feed scheme is adopted to simplify distribution of the local-oscillation (LO) signal. The results show the noise figure of the receiver is less than 5.3dB at 4 GHz bandwidth and the difference of gain of each channel is less than 1dB. The receiver is used in a prototype PMMW imaging system and field tested. The PMMW image of typical scenario is acquired. This works provide a feasible solution schematic for integrated receiver in W-band PMMW imaging system. 1．INTRODUCTIONImaging systems at millimeter wave frequencies have become of increasing interest in recent years.For security applications, threat objects can be viewed through clothing, cardboard and other obscuring materials. In the avionics area, MMW imaging can be used to provide visibility through fog and poor weather conditions during landing approach [1] [2] [3] . Passive imaging depends on both the thermal and the special resolution of the sensor and has a major advantage in these environments since it does not suffer from scattering and multi-path propagation, as compared to active (radar) imaging. As the key technology of the PMMW system, the MMW receiver module is all through the focus of MMW technology research. The development of multi-channel receiver module which operates at W-band and the test result are described in this paper. 2．DESIGN OF MMW MULTI-CHANNEL HETERODYNE RECEIVERThe W band multi-channel receiver adopts double sideband heterodyne receiving regime. As the shown in figure 1, the MMW multi-channel receiver is composed of front-end, intermediate and video