GB579117A - Improvements in or relating to means for increasing the signal to noise ratio in radio transmission systems - Google Patents

Improvements in or relating to means for increasing the signal to noise ratio in radio transmission systems

Info

Publication number
GB579117A
GB579117A GB1643541A GB1643541A GB579117A GB 579117 A GB579117 A GB 579117A GB 1643541 A GB1643541 A GB 1643541A GB 1643541 A GB1643541 A GB 1643541A GB 579117 A GB579117 A GB 579117A
Authority
GB
United Kingdom
Prior art keywords
wave
modulated
carrier
signal
repetitive
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
GB1643541A
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.)
STC PLC
Original Assignee
Standard Telephone and Cables PLC
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 Standard Telephone and Cables PLC filed Critical Standard Telephone and Cables PLC
Priority to GB272430X priority Critical
Priority to GB8798/43A priority patent/GB585827A/en
Publication of GB579117A publication Critical patent/GB579117A/en
Expired legal-status Critical Current

Links

Classifications

    • HELECTRICITY
    • H03BASIC ELECTRONIC CIRCUITRY
    • H03KPULSE TECHNIQUE
    • H03K9/00Demodulating pulses which have been modulated with a continuously-variable signal
    • H03K9/04Demodulating pulses which have been modulated with a continuously-variable signal of position-modulated pulses
    • HELECTRICITY
    • H03BASIC ELECTRONIC CIRCUITRY
    • H03KPULSE TECHNIQUE
    • H03K9/00Demodulating pulses which have been modulated with a continuously-variable signal
    • H03K9/06Demodulating pulses which have been modulated with a continuously-variable signal of frequency- or rate-modulated pulses

Abstract

579,117. Wireless receiving systems. STANDARD TELEPHONES & CABLES, Ltd., and EARP, C. W. Dec. 19, 1941, No. 16435. [Class 40 (v)] A system for the demodulation of a carrier wave of complex wave form repetitive at some predetermined period of time, the repetitive characteristic being modified by the intelligence bearing modulation, consists in dividing the modulated complex carrier wave along two paths having a difference in electrical length equal to the repetition period of the carrier wave or an exact multiple thereof, and combining the signals from the two paths in a balanced modulator or differential detector. Either or both of the paths may include a further modulator for combining the wave with a carrier -wave of constant frequency. The signal from 1, which comprises a series.of pulses which are modulated as regards amplitude, time or duration, is applied through channel A directly to one input of a differential detector D and indirectly by channel B to the second input. Channel B includes a delay network DN which introduces a time delay equal to the interval between the pulses. The output, taken from a low pass filter LF comprises the intelligence which is in the form of a modification of the pulse or repetitive part of the complex carrier. If either or both channels A, B contains a modulator for combining with a constant frequency wave (Fig. 2, not shown) the output consists of the intelligence modulated on to the constant frequency wave. In these arrangements, all components of the repetitive signal combine in the detector to give an output while noise being of random phase does not tend to combine to produce an output. The Specification describes the application of the system to the following types of signal :-modulated carrier and tone telegraph transmission, amplitude, duration and time modulated pulse transmissions, and modulation on a phase or frequency modulated carrier wave.
GB1643541A 1941-12-19 1941-12-19 Improvements in or relating to means for increasing the signal to noise ratio in radio transmission systems Expired GB579117A (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
GB272430X 1941-12-19
GB8798/43A GB585827A (en) 1941-12-19 1943-06-01 Improvements in or relating to the demodulation of time-modulated electrical pulses

Publications (1)

Publication Number Publication Date
GB579117A true GB579117A (en) 1946-07-24

Family

ID=32232364

Family Applications (1)

Application Number Title Priority Date Filing Date
GB1643541A Expired GB579117A (en) 1941-12-19 1941-12-19 Improvements in or relating to means for increasing the signal to noise ratio in radio transmission systems

Country Status (6)

Country Link
US (2) US2426187A (en)
BE (2) BE480687A (en)
CH (1) CH272430A (en)
ES (1) ES177443A1 (en)
FR (2) FR939281A (en)
GB (1) GB579117A (en)

Families Citing this family (28)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2720592A (en) * 1945-11-26 1955-10-11 Howard L Schultz Self-synchronization system
US2677761A (en) * 1945-11-26 1954-05-04 Us Navy Communication system
US2605410A (en) * 1946-08-27 1952-07-29 Rca Corp Pulse-time discriminator
BE479537A (en) * 1947-01-14
US2482782A (en) * 1947-02-13 1949-09-27 Jr George W Lenny Pulse discrimination system
US2761062A (en) * 1947-12-09 1956-08-28 Collins Radio Co Carrier-sensing anti-noise receiving system
US2580148A (en) * 1947-12-09 1951-12-25 Collins Radio Co Antinoise carrier receiving system
US2554112A (en) * 1947-12-18 1951-05-22 Libois Louis Joseph Multiplex transmission system by means of electrical impulses
US3087152A (en) * 1948-07-01 1963-04-23 Aircraft Radio Corp Radar beacon receiver for positionmodulated pulse signals
US2718638A (en) * 1950-01-20 1955-09-20 Itt Signal correlation radio receiver
US2839734A (en) * 1950-05-01 1958-06-17 William T Hanley Frequency slope detection sonar
US2935604A (en) * 1951-12-01 1960-05-03 Toro Michael J Di Long range communication system
US2926243A (en) * 1951-12-11 1960-02-23 Melpar Inc Distance measuring systems
US2841704A (en) * 1952-04-09 1958-07-01 Philco Corp Signal integrating system
US2767259A (en) * 1952-10-01 1956-10-16 Rca Corp Noise compensation in electron beam devices
US2914762A (en) * 1954-02-24 1959-11-24 Raytheon Co Dual channel noise coherence reducers
US3013122A (en) * 1955-01-05 1961-12-12 Gen Electric Multiplex system
US2908812A (en) * 1955-11-09 1959-10-13 George J Laurent Pulse-to-pulse non-linear filters
US2982853A (en) * 1956-07-02 1961-05-02 Research Corp Anti-multipath receiving system
US3042915A (en) * 1957-04-09 1962-07-03 Gen Electric Signal processing arrangement
US3095540A (en) * 1960-11-17 1963-06-25 Avco Corp Intermediate frequency balance bias system
US3205443A (en) * 1961-06-26 1965-09-07 Gen Electronic Lab Inc Interfering signal resolving system
US3305632A (en) * 1963-11-14 1967-02-21 Internat Telemeter Corp Television receiver if frequency stabilizing system
US3267384A (en) * 1964-03-16 1966-08-16 Automatic Elect Lab Phase discriminator of optimum linearity bandwidth
US3539932A (en) * 1966-06-14 1970-11-10 Hoffman Electronics Corp Circuits and methods for measuring the amplitude of plural signals
US3492576A (en) * 1966-07-29 1970-01-27 Bell Telephone Labor Inc Differential phase modulated communication system
US3573642A (en) * 1969-03-10 1971-04-06 Motorola Inc Band-limited fm detector
US4027247A (en) * 1975-11-11 1977-05-31 Bell Telephone Laboratories, Incorporated Receiver especially for use as a diversity combining receiver with channel selection capability

Family Cites Families (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2230212A (en) * 1932-06-20 1941-01-28 Rca Corp Signal receiver
US2226459A (en) * 1935-11-23 1940-12-24 Philco Radio & Television Corp Signal-deriving circuit
GB491728A (en) * 1937-03-10 1938-09-08 Eric Lawrence Casling White Improvements in or relating to circuit arrangements for separating electric signal pulses
NL88393C (en) * 1937-06-18
CH206044A (en) * 1937-07-11 1939-07-15 Sport Ag Method and apparatus for the reception of frequency-modulated oscillations.
BE436744A (en) * 1938-10-21
US2227906A (en) * 1938-10-29 1941-01-07 Rca Corp Envelope current device
US2212420A (en) * 1938-12-15 1940-08-20 Hazeltine Corp Periodic wave repeater
US2266154A (en) * 1939-02-25 1941-12-16 Emi Ltd Thermionic valve circuits
US2239757A (en) * 1940-01-02 1941-04-29 Rca Corp Signal detecting system
US2340432A (en) * 1942-05-23 1944-02-01 Rca Corp Phase modulation receiver

Also Published As

Publication number Publication date
CH272430A (en) 1950-12-15
BE480687A (en)
FR951004A (en) 1949-10-13
BE476627A (en)
FR939281A (en) 1948-11-09
US2426187A (en) 1947-08-26
ES177443A1 (en) 1947-05-01
US2462110A (en) 1949-02-22

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