Sawtooth frequency modulation system including a waveshaping frequency multiplier chain

Claim 2

A generator of frequency modulated signals comprising: means responsive to modulating signals to provide a succession of pulses whose time spacing varies in accordance with the modulating signals, means responsive to said varying time spaced pulses to provide an in-phase square wave output in response to said varying time spaced pulses, means responsive to said square wave for integrating said square wave to provide a symmetrical triangular wave at a first frequency, and means responsive to said triangular wave at said first frequency for providing at the output a triangular wave whose frequency is a multiple of said first frequency.

Claim 3

The combination as claimed in claim 1 wherein said last-mentioned means includes at least one full-wave rectifier circuit.

Claim 4

The combination as claimed in claim 1 wherein said last-mentioned means includes a series of cascaded full-wave rectifier circuits.

Claim 5

A generator of frequency modulated signals comprising in combination: a source of sawtooth waves of substantially constant frequency, a source of modulating signals, at least one wave shape modifying means responsive to the modulating signals and arranged to convert said sawtooth wave to rectangular waves whose width is directly proportional to the instantaneous magnitude of said modulating signals, a second wave shape modifying means arranged to convert the rectangular waves to a succession of pulses whose time spacing varies in accordance with the respective widths of the successive rectangular waves, means responsive to said varying time pulses to provide an in-phase square wave output in response to each of said varying time pulses, means responsive to said square wave for integrating said square wave to provide a symmetrical triangular wave at a first frequency, and full-wave rectifying means responsive to said triangular wave for providing at the output a triangular wave whose frequency is a multiple of said first frequency.

Claim 6

A generator of frequency modulated signals comprising in combination: a source of sawtooth waves of substantially constant frequency, a source of modulating signals, at least one wave shape modifying means responsive to the modulating signals and arranged to convert said sawtooth wave to rectangular waves whose width is directly proportional to the instantaneous magnitude of said modulating signals, a second wave shape modifying means arranged to convert the rectangular waves to a succession of pulses whose time spacing varies in accordance with the respective widths of the successive rectangular waves, means responsive to said varying time pulses to provide an in-phase square wave output in response to each of said varying time pulses, means responsive to said square wave for integrating said square wave to provide a symmetrical triangular wave at a first frequency, and full-wave rectifying means responsive to said triangular wave for providing at the output a triangular wave whose frequency is a multiple of said first frequency.

Claim 7

The combination as claimed in claim 4 wherein the means for integrating integrates only signals above the audio frequency range.

Claim 8

The combination as claimed in claim 4 including a corrector network interposed between a source of modulating signals and said wave shaped modifying means to attenuate the components of the modulating potentials in the frequency range from 13.5 Hz to 2.1 kHz.

Claim 9

The combination as claimed in claim 4 wherein said full-wave rectifying means includes a series of full-wave rectifiers connected in cascade.

Claim 10

The combination as claimed in claim 7 wherein said cascaded full-wave rectifiers operate to provide multiplication within the approximate frequency range below about 30 MHz.

Claim 11

The combination as claimed in claim 7 and including a crystal filter responsive to the output of said series of full-wave rectifiers which rejects the fundamental and all harmonics except the third to provide an extra multiplication of said triangular wave output from said rectifier as well as filtering.

Claim 12

The combination as claimed in claim 9 above wherein the output of said crystal is applied to a harmonic multiplier.