GB2019145A - Improvements in or relating to frequency modulators - Google Patents

Improvements in or relating to frequency modulators

Info

Publication number
GB2019145A
GB2019145A GB7918186A GB7918186A GB2019145A GB 2019145 A GB2019145 A GB 2019145A GB 7918186 A GB7918186 A GB 7918186A GB 7918186 A GB7918186 A GB 7918186A GB 2019145 A GB2019145 A GB 2019145A
Authority
GB
United Kingdom
Prior art keywords
signal
oscillator
responsive
amplitude
modulating
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
GB7918186A
Other versions
GB2019145B (en
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Plessey Co Ltd
Original Assignee
Plessey Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Plessey Co Ltd filed Critical Plessey Co Ltd
Priority to GB7918186A priority Critical patent/GB2019145B/en
Publication of GB2019145A publication Critical patent/GB2019145A/en
Application granted granted Critical
Publication of GB2019145B publication Critical patent/GB2019145B/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03C—MODULATION
    • H03C3/00—Angle modulation
    • H03C3/02—Details
    • H03C3/09—Modifications of modulator for regulating the mean frequency
    • H03C3/0908—Modifications of modulator for regulating the mean frequency using a phase locked loop
    • H03C3/0958—Modifications of modulator for regulating the mean frequency using a phase locked loop applying frequency modulation by varying the characteristics of the voltage controlled oscillator
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03C—MODULATION
    • H03C3/00—Angle modulation
    • H03C3/02—Details
    • H03C3/08—Modifications of modulator to linearise modulation, e.g. by feedback, and clearly applicable to more than one type of modulator
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03C—MODULATION
    • H03C2200/00—Indexing scheme relating to details of modulators or modulation methods covered by H03C
    • H03C2200/0037—Functional aspects of modulators
    • H03C2200/005—Modulation sensitivity

Landscapes

  • Amplitude Modulation (AREA)

Abstract

A frequency modulator comprises an oscillator 1, modulating signal control means e.g. an amplifier 12 via which a modulating signal at 11 is fed to the oscillator to produce a corresponding frequency modulation on the output signal from the oscillator, a discriminator e.g. a monostable circuit 15 responsive to the frequency modulation for producing a corresponding amplitude signal and a comparator 18 responsive to the corresponding amplitude signal and to the modulating signal for providing a control signal which is fed back to control the gain provided by the signal control means 12 so as to maintain constant the amplitude of the amplitude signal with respect to the modulating signal whereby operation of the modulator is linearised. A phase sensitive detector 20 is responsive to the modulation signal squared at 21 to full wave rectify the error output of comparator, which is integrated at 22 to provide the gain control voltage. Optionally, an inverted and attenuated version of the modulation signal may be combined with the demodulated signal to obtain the error signal for the detector 20. <IMAGE>
GB7918186A 1978-03-10 1979-05-24 Frequency modulators Expired GB2019145B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB7918186A GB2019145B (en) 1978-03-10 1979-05-24 Frequency modulators

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB952078 1978-03-10
GB7918186A GB2019145B (en) 1978-03-10 1979-05-24 Frequency modulators

Publications (2)

Publication Number Publication Date
GB2019145A true GB2019145A (en) 1979-10-24
GB2019145B GB2019145B (en) 1982-07-21

Family

ID=26242990

Family Applications (1)

Application Number Title Priority Date Filing Date
GB7918186A Expired GB2019145B (en) 1978-03-10 1979-05-24 Frequency modulators

Country Status (1)

Country Link
GB (1) GB2019145B (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2568430A1 (en) * 1984-07-27 1986-01-31 Alcatel Thomson Faisceaux Transceiver set with homodyne reception
FR2616285A1 (en) * 1987-06-05 1988-12-09 Thomson Semiconducteurs DEVICE FOR THE MINIMAL AND MAXIMUM FREQUENCY ADJUSTMENT OF A FREQUENCY MODULE VIDEO SIGNAL
FR2660814A1 (en) * 1990-04-06 1991-10-11 Schlumberger Ind Sa Frequency-summing circuit
WO2004034565A2 (en) * 2002-10-08 2004-04-22 M/A-Com, Inc. Apparatus and methods for wideband signal processing
US7545865B2 (en) 2002-12-03 2009-06-09 M/A-Com, Inc. Apparatus, methods and articles of manufacture for wideband signal processing

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2568430A1 (en) * 1984-07-27 1986-01-31 Alcatel Thomson Faisceaux Transceiver set with homodyne reception
FR2616285A1 (en) * 1987-06-05 1988-12-09 Thomson Semiconducteurs DEVICE FOR THE MINIMAL AND MAXIMUM FREQUENCY ADJUSTMENT OF A FREQUENCY MODULE VIDEO SIGNAL
EP0296989A1 (en) * 1987-06-05 1988-12-28 STMicroelectronics S.A. Device for adjusting the minimal and maximal frequencies of a frequency modulated video signal
US4918529A (en) * 1987-06-05 1990-04-17 Sgs-Thomson Microelectronics S.A. Device for setting minimal and maximal frequencies of a frequency modulated video signal
FR2660814A1 (en) * 1990-04-06 1991-10-11 Schlumberger Ind Sa Frequency-summing circuit
WO2004034565A2 (en) * 2002-10-08 2004-04-22 M/A-Com, Inc. Apparatus and methods for wideband signal processing
WO2004034565A3 (en) * 2002-10-08 2004-07-22 Ma Com Inc Apparatus and methods for wideband signal processing
US7545865B2 (en) 2002-12-03 2009-06-09 M/A-Com, Inc. Apparatus, methods and articles of manufacture for wideband signal processing

Also Published As

Publication number Publication date
GB2019145B (en) 1982-07-21

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Legal Events

Date Code Title Description
PCNP Patent ceased through non-payment of renewal fee