US1913428A - Radio receiver circuit - Google Patents

Radio receiver circuit Download PDF

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Publication number
US1913428A
US1913428A US346857A US34685729A US1913428A US 1913428 A US1913428 A US 1913428A US 346857 A US346857 A US 346857A US 34685729 A US34685729 A US 34685729A US 1913428 A US1913428 A US 1913428A
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US
United States
Prior art keywords
waves
amplitude
received
receivers
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 - Lifetime
Application number
US346857A
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English (en)
Inventor
Bruce Edmond
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.)
AT&T Corp
Original Assignee
Bell Telephone Laboratories Inc
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
Priority to BE367572D priority Critical patent/BE367572A/xx
Application filed by Bell Telephone Laboratories Inc filed Critical Bell Telephone Laboratories Inc
Priority to US346857A priority patent/US1913428A/en
Priority to FR698480D priority patent/FR698480A/fr
Priority to GB7204/30A priority patent/GB349971A/en
Application granted granted Critical
Publication of US1913428A publication Critical patent/US1913428A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
    • H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
    • H04B7/08—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the receiving station
    • H04B7/0837—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the receiving station using pre-detection combining

Definitions

  • This invention relates to radio receiving circuits and hasfor an obi ect to reduce the effects of fading, that is, variations in intensity of the received wave.
  • a specific embodiment ofthis invention a plurality of geographically separated antennae are arranged to receive waves from the same transmitter.
  • V detector is associated with each ofthe antennae andthe received wavesare combined impressed upon a low frequency detector'in Whichthey are detected to yield thesignal.
  • a resistance element is included in the l plate circuit of the low frequency detector and the grid biasing potentials of the high frequency detectors are controlled by thedire ct current potential drop across this resistance;
  • the high frequency detectors are operated near the critical points of their grid potentialplate currentcharacteristics, so thatany material increase in the negative grid bias will render them inoperative for incoming Waves of small amplitude.
  • a a i The biasing potential due to the drop across the resistance in the low frequency detector will be determinedat any instant by thesignal fromthe antenna in whichtheoutput'has the largest amplitude and will block thecdeteeters associated with those antennae in which the amplitude of the output is materially sinaller.
  • i 1 InZthe drawingthere isshownoneembodiment of the invention in a system employing three antennae 1,2 and 3 which are associated withthe high frequency. detectors 4,5 and 6, respectively, of the electric discharge or audiontype.
  • a j i :Ccupling to the :inputs of the detectors is provided through the step-up auto+trans formers 7, 8 and9 connected across which are the tuning condensers 10, 11, and .12.
  • One secondary terminalof each of the transformers 7 8 and 9 is connected 11 01 17118 gr-id of the .correspondingdetector.
  • the common. primary andsecondary terminals of the transformers are connected togetherand through the blockingconc lenser 13 to the groundfor thecommon cathode circuit of the detectors.
  • the anodes of thedetectors are connected together andto one terminal of the primary winding of the transformerll.
  • the other terminal of this Winding is connected through the secondary of transformer 15 and the space cur-rentbattery 16 to the common cathode cirsuit to the detectors.
  • a heterodyne wave is supplied from the oscillator 17 to the anode circuit of the detectorsthrough the trans former 15.
  • V i i The secondary winding of the transformer 14 is connected to the inputterminals'o f an intermediate frequency filter and amplifier 18,
  • the outputof the amplifier 18 is connected to the grid circuit of a low frequency detector herein shown, by way of'example, as an electric or space discharge device 19.
  • the output or anodeicircuit of the detector comprises in series, the space current battery 20, receiver 21 and resistance element 22.
  • Theibattery, 24 supplies a normal biasing potentialto the gridsof tubes 4, 5 and 6.
  • the antennae are so arranged geographicallythat fading conditions-at each varydifferently.
  • the ireceiyed waves are impressed on the grids ofgtherespective detectors at, 5 and6 and are combined in the common anode circuit with oscillations supplied by the local oscillator 17
  • the resultant intermediate frequency waves are amplified in the amplifier 18 and impressed on the low frequency detector 19, wherein they are detected to yield the signal wave.
  • the system is so designed, particularly with regard to the choice of voltage from the biasing battery 2d-and control voltage supplied-by the resistance 22, that a wave of any material amplitude received in any of the antennae 1, 2 or 3 will impress through the control connection 23 such a negative potential upon the grids of detectors 4 and 5, 4 and 6, or 5and 6, as the case may be, as to block them for waves ofv substantially smaller amplitude.
  • the system will operate so that at any instant the antenna receiving the wave of largest amplitude will be the only one which will supply a wave through the circuit to the receiver 21, the high frequency detectors associated with the other antennae being rendered inoperative by the action of the control connection 23 to prevent the transmission of waves through them.
  • a plurality of antennae an electric discharge device coupled to each of said antennae to received waves therefrom, means for producing a control potential which is a function of the amplitude of the wave output from each of said devices, and means responsive to said potential for controlling said devices to render inoperative at least for the transmission of waves of small amplitude those in which the amplitude of the received wave is small compared to that of the received wave in another.
  • a circuit including an electric discharge device so adjusted that said device operates near the critical point of its transmission characteristic coupled to each of said antennae, means for producing a unidirectional potential which is a function of the amplitude of the wave received in each of said antennae, and means responsive to said potential for controlling said discharge devices to render inoperative for the transmission of waves of amplitude of the order of those received in the respective antennae those of said devices in which the amplitude of the received wave is small compared to that of the received wave in another of said devices.
  • a radio receiving system comprising a plurality of antennae, a local source of oscillations, an electric discharge detector coupled to each of said antennae for combining the received wave with the local oscillations, said detectors having transmission characteris tics with critical points at which the devices are substantially inoperative for the transmission of waves of small amplitude being operated near said critical points of their characteristics, an intermediate frequency amplifier connected to selectively repeat the detected waves from said detectors, an electric discharge detector for detecting the Waves from said intermediate frequency ainplifier, means for producing a unidirectional potential proportional to the direct current output current of the last mentioned detector, and means for impressing said unidirectional potential between the electrodes of the first mentioned detectors to render inoperative forthe transmission of waves of small amplitude those in which the amplitudes of the received waves are small compared to that of the received wave in an other of said detectors.
  • the method of operating a radio receiving system having plurality of antennae and an electric discharge device coupled to each antenna which comprises producing a unidirectional potential which is a function of the amplitude of the wave of largest amplitude received at any instant in any of said devices, and utilizing said potential to so affect the discharge devices in which the received waves are of substantially smaller amplitude that they are rendered substantially inoperative for the transmission of waves of said small amplitude.
  • the method of radio reception which comprises receiving at a plurality of separate points, waves carrying the same signal, changing the frequency of the received waves, detecting the waves of changed frequency, producing from the detected waves a unidirectional potential, and controlling in accordance with said potential, the transmission of the received waves to substantially suppress" all but that one of the received' waves having at any instant the largest amplitude.
  • Aradio receiver comprising a plurality of antennae so. located that fading conditions vary differently at each, frequency changing means including an electric discharge modulator coupled to each antenna to reduce the frequency of the received waves, means for selectively amplifying the waves of reduced frequency to the substantial exclusion of waves of higher frequency, and means for detecting the selectively amplified waves to produce waves of signal frequency, the detectingmeans being provided with connectlOHS to said electricvdischarge modulators to apply thereto a voltage of such magnitude and sign as to render substantially inoperative for the translating of waves of small amplitude the modulators receiving waves of substantially smaller amplitude than the Waves received in another of the modulators.
  • a plurality of antenna so related to each other that the received waves vary differently at the several receivers with variationsin transmission conditions that reception conditionsvary differently at i each, a plurality of electric discharge devices each having an anode, a cathode and a control element, means for supplying the waves received in each of said antennae to a .corresponding one of said devices, means for pro ducing a unidirectional electromotive force having at any instant an amplitude which is function of the amplitude of the received waves, means for impressing said electromotive force upon'the control electrodes ofsaid devices to so affect the transmission characteristics thereofthat those devices WlllCh the instant are receiving waves of sub stantially lower amplitudes than the waves beingreceived by another device are rendered substantially inoperative for the trans mission of waves of said lower amplitudes, and a signal receiving circuit connected to receive waves transmitted by any of said devices.
  • a plurality of receivers each receiving the same signal and so related to each other that the received signals vary differently at the several receivers with variations in transmission conditions, a signal circuit common to said receivers, and means responsive to the amplitude of the outputs of saidreceivers for automatically controlling the gain of at least one i of said receivers to. render substantially ina operative said one of said receivers when its output is materially lower than that of another of said receivers.
  • each receiver comprising an electric discharge device, a signal circuit common to said receivers, means for producing a uniof one of said receivers in response to the amplitude of the signal received in at least one of the other of said signal receivers to render substantially inoperative said one of said receivers when the amplitude of the signal wave received thereby is materially lower than the amplitude of the signal Wave received by said other of said signal receivers.
  • a plurality of receivers each receiving the same signal and so related to each other that the received signals. varydiiierently at the several receivers with variations in transmission conditions, and means for automatically controlling over a continuous rangethe gain of at least one of said receivers in response to the amplitude of the signal received in at least one of the respective others of said signal receivers to render substantially inoperative said one of said receivers when the amplitude of the signal wave received thereby is materially lower than the amplitude of the signal received by said one of the respective others of said signal receivers.
  • a plurality of radio signal receivers means for combining the sig nal output of said receivers,and means for automatically controlling over a continuous range the gain of one of said receivers in response to the amplitude of the signal from said means for combining the signal output of said receivers to render substantially inoperative said one of said receivers when the amplitude of the signal Wave received thereby is materially lower than the amplitude of the signal wave received by another of said signal receivers.
  • a plurality of antennae an electric discharge device coupled to each of said antennae to receive waves therefrom, means for producing a control potential which is a function of the amplitude of the wave output from each of said devices, and means responsive to said potential for controlling said devices to render inoperative at least for the transmission of waves of small amplitude those in which the amplitude of the received wave is small compared to that of the received. wave in another.
  • the method of operating a radio receiving system having a plurality of antennae and an electric discharge device coupled to each antenna which comprises producing a unidirectional potential which is a function of the amplitude of the wave of largest amplitude received at any instant in any of said devices, and utilizing said potential to so affect the discharge devices in which the received waves are of substantially smaller amplitude that they are rendered substantially inoperative for the transmission of waves of said small amplitude.
  • the method of radio reception which comprises receiving at a plurality of separate points, waves carrying the same signal, changing the frequency of the received waves, detecting the'waves of changed frequency, producing from the detected waves a unidirectional potential, and controlling, in accordance with said potential, the transmission of the received waves to substantially suppress all but that one of the received waves having at any instant the largest amplitude.
  • a plurality of antennae so related to each other that the received waves vary differently at the several receivers with variations in transmission conditions that reception conditions vary differently at each, a plurality of electric discharge devices each having an anode, a cathode and a control element, means for supplying the waves received in each of said antennae to a.
  • means for producing a unidirectional electromotive force having at any instant an amplitude which is a function of the amplitude of the received waves means for impressing said electromotive force upon the control electrodes of said devices to so affect the transmission characteristics thereof that those devices which at the instant are receiving Waves of substantially lower amplitudes than the waves being received by another device are rendered substantially inoperative for the transmission of waves of said lower amplitudes, and a signal receiving circuit connected to receive waves transmitted by any of said devices.
  • a plurality of receivers each receiving the same signal and so related to each other that the received signals vary differently at the several receivers with variations in transmission conditions, a signal circuit common to said receivers, and means responsive to the amplitude of the outputs of said receivers for automatically controlling the gain of at least one of said receivers to render substantially inoperative said one of said receivers when its output is materially lower than that of another of said receivers.
  • each receiver comprising an electric discharge device, a signal circuit common to said receivers, means for producing a unidirectional potential which is a function of the amplitude of the input to said signal circuit, and means for impressing said unidirectional potential between the electrodes of said electric discharge devices to render inoperative those of said devices in which the amplitude of the received wave issmall compared with that of the received wave in another of said devices.
  • a plurality of signal receivers and means for automatically controlling over acontinuous range the gain of one of said receivers in response to the amplitude of the signal received in at least one of the other of said signal receivers to render substantially inoperative said one of said receivers when the amplitude of the signal wave received thereby is materially lower than the amplitude of the signal wave received by said other of said signal receivers.
  • a plurality of receivers each receiving the same signal and so related to each other that the received signals vary differently at the several receivers with variations in transmission conditions, and means for automatically controlling over a continuous range the gain of at least one of said receivers in response to the amplitude of the signal received in at least one of the respective others of said signal receivers to render substantially inoperative said one of said receivers when the amplitude of the signal wave received thereby is materially lower than the amplitude of the signal received by said one of the respective others of said signal receivers.
  • a plurality of radio signal receivers means for combining the signal output of said receivers, and means for automatically controlling over a continuous range the gain of one of said receivers in response to the amplitude of the signal from said means for combining the signal output of said receivers to render substantially inoperative said one of said receivers when the amplitude of the signal wave received thereby is materially lower than the amplitude of the signal wave received by another of said signal receivers.

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  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Variable-Direction Aerials And Aerial Arrays (AREA)
  • Mobile Radio Communication Systems (AREA)
US346857A 1929-03-14 1929-03-14 Radio receiver circuit Expired - Lifetime US1913428A (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
BE367572D BE367572A (cs) 1929-03-14
US346857A US1913428A (en) 1929-03-14 1929-03-14 Radio receiver circuit
FR698480D FR698480A (fr) 1929-03-14 1930-01-07 Perfectionnements aux systèmes récepteurs pour transmissions radiophoniques
GB7204/30A GB349971A (en) 1929-03-14 1930-03-05 Improvements in or relating to radio receiving systems

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US346857A US1913428A (en) 1929-03-14 1929-03-14 Radio receiver circuit

Publications (1)

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US1913428A true US1913428A (en) 1933-06-13

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US346857A Expired - Lifetime US1913428A (en) 1929-03-14 1929-03-14 Radio receiver circuit

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US (1) US1913428A (cs)
BE (1) BE367572A (cs)
FR (1) FR698480A (cs)
GB (1) GB349971A (cs)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2430983A (en) * 1939-07-24 1947-11-18 United Geophysical Company Inc Seismic amplifying system
US2447057A (en) * 1943-05-06 1948-08-17 Rca Corp Diversity receiving system
US2504341A (en) * 1946-12-27 1950-04-18 Rca Corp Diversity receiver
US2959674A (en) * 1957-07-02 1960-11-08 Thomas R O'meara Gain control for phase and gain matched multi-channel radio receivers

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2430983A (en) * 1939-07-24 1947-11-18 United Geophysical Company Inc Seismic amplifying system
US2447057A (en) * 1943-05-06 1948-08-17 Rca Corp Diversity receiving system
US2504341A (en) * 1946-12-27 1950-04-18 Rca Corp Diversity receiver
US2959674A (en) * 1957-07-02 1960-11-08 Thomas R O'meara Gain control for phase and gain matched multi-channel radio receivers

Also Published As

Publication number Publication date
FR698480A (fr) 1931-01-31
BE367572A (cs)
GB349971A (en) 1931-06-05

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