Digitally controlled rf sweep generator

Claim 2

A digitally controlled RF linear sweep generator, comprising: means for changing the phase of an input RF signal; means connected to said means for changing the phase for changing the rate of phase shift of an input RF signal; a binary counter; and said means for changing connected to said binary counter and changing the rate of said phase shift of said RF signal in response to a change in the accumulated count of said counter.

Claim 3

The sweep generator of claim 1, including: means connected to said binary counter for driving said counter and changing the accumulated count; and said counter being incremented at a parabolic rate with respect to time and changing the rate of phase shift parabolically.

Claim 4

The sweep generator of claim 2, wherein said RF signal changes linearly with respect to time in respOnse to said parabolic rate of change of said phase shift and said frequency sweep excursion extends from a maximum frequency corresponding to a maximum rate of phase shift in a first direction, through the RF input frequency corresponding to zero rate of phase shift, to a minimum frequency corresponding to a maximum rate of phase shift in a second direction.

Claim 5

A digitally controlled RF linear sweep generator, means for changing the phase of an input RF signal; means connected to said means for changing the phase for changing the rate of phase shift of an input RF signal; a binary counter; said means for changing connected to said binary counter and changing the rate of said phase shift of said RF signal in response to a change in the accumulated count of said counter; said means for changing the phase is a digitally stepped phase shifter; said means for driving said binary counter comprises a pulse source for producing a plurality of binarily related pulse trains within a unit time period; gating means for selectively connecting said pulse trains to said counter; a control register connected to said gating means and to said pulse source; said control register generating digital commands to said gating means in response to said pulse source; and said gating means selectively connecting said pulse trains to said counter in response to generated digital commands.

Claim 6

A digitally controlled RF linear sweep generator, means for changing the phase of an input RF signal; means connected to said means for changing the phase for changing the rate of phase shift of an input RF signal; a binary counter; said means for changing connected to said binary counter and changing the rate of said phase shift of said RF signal in response to a change in the accumulated count of said counter; said means for changing the phase is a digitally stepped phase shifter; said means for driving said binary counter comprises a pulse source for producing a plurality of binarily related pulse trains within a unit time period; gating means for selectively connecting said pulse trains to said counter; a control register connected to said gating means and to said pulse source; said control register generating digital commands to said gating means in response to said pulse source; and said gating means selectively connecting said pulse trains to said counter in response to generated digital commands.

Claim 7

The sweep generator of claim 4, including: an up-down command connected to said register and to said binary counter; and said up-down command reversing the counting direction of said binary counter and said register when said sweep frequency is equal to said RF input signal frequency and when said sweep frequency is at its minimum frequency.

Claim 8

The sweep generator of claim 5, wherein: said up-down command reverse the counting direction of said binary counter from down to up, the counting direction of said register from up to down when said sweep frequency is at its sweep minimum; and said up-down command reverses the counting direction of said register from down to up and said binary counter from up to down when said sweep frequency is at said RF input frequency.

Claim 9

The sweep generator of claim 6, including: a comparator connected to said register and to said up-down command; said up-down command reversing said counting direction of said binary counter from up to down in response to a register count of 00000 sensed by said comparator; said up-down command reversing said counting direction of said binary counter from down to up in response to a register count of ''''N'''' sensed by said comparator; and where ''''N'''' is a maximum count having a value functionally related to the number of unit time periods in the sweep interval.

Claim 10

The sweep generator of claim 7, wherein: said gating means includes a plurality of ''''and'''' gates; said pulse source includes a plurality of output terminals, and each of said binarily related pulse trains appears on a respective terminal; said pulse source lowest frequency signal being directly connected to said control register input; and each of said ''''and'''' gates having a first input connected to a respective pulse source terminal and a second input connected to the output of said register with the lowest frequency pulse terminal directly connected to the least significant bit in said register and each successive ''''and'''' gate having its inputs connected to the next successively higher frequency pulse terminal and the next more significant bit in said register.

Claim 11

The sweep generator of claim 8, wherein said control register count is incremented by two counts for each pulse received by said control register from said pulse source.

Claim 12

The sweep generator of claim 4, wherein said control register count is incremented by two counts for each pulse received by said control register from said pulse source.