PCT No. PCT / GB95 / 01607 Sec. 371 Date Dec. 10, 1997 Sec. 102(e) Date Dec. 10, 1997 PCT Filed Jul. 7, 1995 PCT Pub. No. WO97 / 03367 PCT Pub. Date Jan. 30, 1997A circuit module for a
phased array radar (10) incorporates
radar frequency (RF) mixers (54a, 54b) connected to an RF splitter / combiner (52) and to in-phase and quadrature RF reference signals. The RF mixers (54a, 54b) are also connected to
intermediate frequency (IF)
processing circuitry (60 to 68) providing for
phase control of RF signals and IF reference signals. In transmission mode, the RF mixer (54a, 54b) receive phase-controlled, digitally synthesised IF signals from
clock-activated generators (68a, 68b). Their outputs are combined at the RF splitter / combiner (52) to provide single
sideband upconversion of the phase-controlled IF signals. In reception mode, the RF splitter / combiner (52) and the RF mixers (54a, 54b) act as an image rejection mixer circuit in which the phase-controlled IF signals are
local oscillator signals.
Beamforming is carried out by
computer control of the IF phase together with, in the case of reception, analogue or digital summation of output signals from an array of modules (12).