초록 ▼

A secondary surveillance radar e.g. a Mode-S radar, has a controllable power source in which first and second in-phase r.f. signals are derived from a source (6) by a power splitter (11), and a phase shifter (32) adjusts selectively the relative phase of the signals, so that after amplification by m

A secondary surveillance radar e.g. a Mode-S radar, has a controllable power source in which first and second in-phase r.f. signals are derived from a source (6) by a power splitter (11), and a phase shifter (32) adjusts selectively the relative phase of the signals, so that after amplification by main amplifiers (21, 22) and combination by power comber (23), the resultant power level can be controlled by the phase shift produced by the phase shifter (32).

대표청구항 ▼

[ We claim:] [1.] A secondary surveillance radar including:a transmitter to transmit radar signals that interrogate transponders on remote targets;a receiver to receive returns from the interrogated transponders on the targets; anda controllable power source to produce r.f. signals for the transmitt

[ We claim:] [1.] A secondary surveillance radar including:a transmitter to transmit radar signals that interrogate transponders on remote targets;a receiver to receive returns from the interrogated transponders on the targets; anda controllable power source to produce r.f. signals for the transmitter, comprising circuitry to produce first and second r.f. signals having a predetermined phase relationship; a phase setter that sets the phase relationship between first and second signals selectively; first and second power amplifiers to amplify the first and second signals respectively; and a power combiner to combine the first and second signals amplified by the amplifiers whereby to provide an amplified r.f. output signal of a power dependent upon the phase relationship set by the phase setter.