초록 ▼

A wave-form generator drives a number of microwave generating devices each operating at different frequency bands. The output of each microwave generator is connected to its own transmission channel of limited bandwidth which contains all the non-linear components necessary for transmission such as

A wave-form generator drives a number of microwave generating devices each operating at different frequency bands. The output of each microwave generator is connected to its own transmission channel of limited bandwidth which contains all the non-linear components necessary for transmission such as an amplifier, T/R switch, rotary joint and beam switch. These individual channels are finally combined onto a common wideband channel which contains only substantially linear components such as a single waveguide and the antenna itself. Because of the isolation between channels there is little or no opportunity for the generation of harmonics or intermodulation distortions which would otherwise occur in a transmitter capable of operating over a very wide bandwidth.

대표청구항 ▼

1. A Doppler radar, comprising:a plurality of individual sources of microwave energy designed to operate over different frequency bands each of one octave or less spaced so that in combination said sources are capable of operating over a frequency band or more than one octave; a pulse generator mean

1. A Doppler radar, comprising:a plurality of individual sources of microwave energy designed to operate over different frequency bands each of one octave or less spaced so that in combination said sources are capable of operating over a frequency band or more than one octave; a pulse generator means connected to the individual said microwave sources for driving the individual said microwave sources to produce simultaneous pulses at different frequencies within their individual said frequency bands; a first plurality of individual channels leading from the respective said sources and having relatively non-linear characteristics; a common channel having relatively linear characteristics; an antenna means connected to one end of said common channel for transmitting a signal fed thereto via said common channel in a single beam direction and for receiving the transmitted signal after reflection from a remote target and feeding the received signal to said common channel; a plurality of individual receivers designed to operate in the respective said different frequency bands; a second plurality of separate channels for carrying signal components in the respective said different frequency bands and connected to the respective inputs of said plurality of receivers; means, connected to the other end of said common channel, for combining the outputs from the individual channels of said first plurality of separate channels onto said common channel and for separating a received signal in said common channel into said different frequency bands and feeding same to the respective individual channels of said second plurality of channels; and, velocity deduction means connected to receive an output from each receiver and to deduce therefrom a Doppler frequency shift of that component of the received signal in the appropriate frequency band. 2. A Doppler radar according to claim 1 including means for combining outputs from said velocity deduction means to reduce any ambiguities in the Doppler frequency shift.3. A Doppler radar system as defined in claim 1 wherein said velocity deduction means is further connected to receive the output of said pulse generator means.4. A Doppler radar as defined in claim 1, wherein said velocity deduction means includes a plurality of Doppler processing circuits, each connected to receive the output of a respective one of said receivers and the output of said pulse generator means.5. A Doppler radar as defined in claim 1 wherein said means for combining and for separating includes: a plurality of circulators, each having a first port connected to a respective one of said first plurality of separate channels, a second port connected a respective one of said second plurality of separate channels, and a third port; and a crossover network connected between each of said third ports and said common channel.