GB1339701A - Repeaters for use in frequency modulated radio relay systems - Google Patents

Repeaters for use in frequency modulated radio relay systems

Info

Publication number
GB1339701A
GB1339701A GB5923471A GB5923471A GB1339701A GB 1339701 A GB1339701 A GB 1339701A GB 5923471 A GB5923471 A GB 5923471A GB 5923471 A GB5923471 A GB 5923471A GB 1339701 A GB1339701 A GB 1339701A
Authority
GB
United Kingdom
Prior art keywords
output
repeater
comparator
reference oscillator
signal
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.)
Expired
Application number
GB5923471A
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.)
Leonardo SpA
Original Assignee
Selenia Industrie Elettroniche Associate SpA
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 Selenia Industrie Elettroniche Associate SpA filed Critical Selenia Industrie Elettroniche Associate SpA
Publication of GB1339701A publication Critical patent/GB1339701A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/14—Relay systems
    • H04B7/15—Active relay systems
    • H04B7/155—Ground-based stations

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Transmitters (AREA)
  • Radio Relay Systems (AREA)

Abstract

1339701 F.M. repeaters; automatic frequency control SELENIA INDUSTRIE ELETTRONICHE ASSOCIATE SpA 21 Dec 1971 [10 Feb 1971] 59234/71 Headings H4L and H3A An F.M. repeater for a radio relay system comprises a frequency changer CF responsive to the repeater input signal f 1 and the fed-back repeater output signal f 2 to give an intermediate frequency signal f i which is amplified at AFI and applied to a phase comparator CP which also receives the output f<SP>1</SP> i of a controllable reference oscillator OSC; and a low-pass filter PB passes the comparator CP output to the control input of a voltage controlled oscillator VCO generating the output signal f 2 . Since f<SP>1</SP> i from the reference oscillator is a single frequency, and the feedback loop acts to minimize, the phase difference between f i and f<SP>1</SP> i , the comparator output tends to modulate the output signal f 2 with the same modulation as f 1 . Incoming information may be extracted at the filter output PB, and additional modulating information may be introduced by modulating the reference oscillator.
GB5923471A 1971-02-10 1971-12-21 Repeaters for use in frequency modulated radio relay systems Expired GB1339701A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
IT4831171 1971-02-10

Publications (1)

Publication Number Publication Date
GB1339701A true GB1339701A (en) 1973-12-05

Family

ID=11265817

Family Applications (1)

Application Number Title Priority Date Filing Date
GB5923471A Expired GB1339701A (en) 1971-02-10 1971-12-21 Repeaters for use in frequency modulated radio relay systems

Country Status (4)

Country Link
DE (1) DE2206023A1 (en)
FR (1) FR2124228A1 (en)
GB (1) GB1339701A (en)
NL (1) NL7200636A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2122456A (en) * 1982-05-19 1984-01-11 Ronald R White Method of an apparatus for duplex communications

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2122456A (en) * 1982-05-19 1984-01-11 Ronald R White Method of an apparatus for duplex communications

Also Published As

Publication number Publication date
NL7200636A (en) 1972-08-14
FR2124228A1 (en) 1972-09-22
DE2206023A1 (en) 1972-08-31

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Legal Events

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