US2384456A - Radio receiving system - Google Patents

Radio receiving system Download PDF

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Publication number
US2384456A
US2384456A US536925A US53692544A US2384456A US 2384456 A US2384456 A US 2384456A US 536925 A US536925 A US 536925A US 53692544 A US53692544 A US 53692544A US 2384456 A US2384456 A US 2384456A
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US
United States
Prior art keywords
channel
tube
marking
channels
tubes
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
US536925A
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English (en)
Inventor
James R Davey
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 BE481301D priority Critical patent/BE481301A/xx
Priority to NL79786D priority patent/NL79786C/xx
Priority to FR959580D priority patent/FR959580A/fr
Application filed by Bell Telephone Laboratories Inc filed Critical Bell Telephone Laboratories Inc
Priority to US536925A priority patent/US2384456A/en
Application granted granted Critical
Publication of US2384456A publication Critical patent/US2384456A/en
Priority to GB20989/47A priority patent/GB635590A/en
Priority to CH265990D priority patent/CH265990A/de
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L1/00—Arrangements for detecting or preventing errors in the information received
    • H04L1/02—Arrangements for detecting or preventing errors in the information received by diversity reception
    • H04L1/06—Arrangements for detecting or preventing errors in the information received by diversity reception using space diversity
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00—Modulated-carrier systems
    • H04L27/10—Frequency-modulated carrier systems, i.e. using frequency-shift keying
    • H04L27/14—Demodulator circuits; Receiver circuits
    • H04L27/144—Demodulator circuits; Receiver circuits with demodulation using spectral properties of the received signal, e.g. by using frequency selective- or frequency sensitive elements
    • H04L27/148—Demodulator circuits; Receiver circuits with demodulation using spectral properties of the received signal, e.g. by using frequency selective- or frequency sensitive elements using filters, including PLL-type filters

Definitions

  • Another object is to provide a diversity radio receiving system with improved means for separately detecting noise currents in each of the diversity channels.
  • a radio receiving system for receiving, for example, marking and spacing radio-telegraph signals having different frequencies
  • the received currents of the two frequencies are first subjected to amplitude limitation and are then selectively amplified in separate amplifiers.
  • An electronic tube is connected to the center tap of a large resistance bridged between the control grids of the marking and spacing output amplifier tubes for detecting average noise currents. Since the amplitude limitation is performed at a point in the circuit ahead-of the resistance, a change in the amplitude of the noise currents represents by itself a change in the signal-to-noise ratio.
  • the differential between the currents in the marking and spacing paths becomes low thereby increasing the voltage at the center tap of the resistance.
  • This causes an increase in the plate current of the electronic tube which, in one embodiment of the invention, is utilized for energizing a cut-off relay to remove the voltage normally applied to the screen grids of the marking and spacing output amplifier tubes.
  • This method of noise detection is applied to a diversity radio receiving system by connecting a similar center tapped resistance with corresponding tube and relay circuits in each diversity channel. The cutofi relays in these diversity channels are energized differentially to out off only the noisiest channel thereby avoiding the possibility of disabling all the diversity channels at the same time.
  • the receiving relay of a diversity radio receiving system is supplied with approximately constant current from the diversity signal input circuits by connecting'the output of the electronic tube, described above, in each'diversity channel to a series of amplifying tubes.
  • the output of these amplifying tubes in each channel is applied to reduce the screen grid voltage of the output amplifier tubes in'that channel and to increase the screen grid voltage of the output amplfier tubes in the other channel.
  • noise currents in one channel will cause a reduction in the gain of that channel and a corresponding increase in the'gain of the other channel so that the value of the combined currents supplied by both channels to the receiving relay remains approximately constant.
  • a relatively larg resistance in the'form of two equal series-connected resistances I3 and I4 is bridged across the control grids of the marking and spacing output amplifier tubes 1 and I2.
  • the instantaneous value of the voltage at the midpoint I! between the resistances l3 and M will be the average of the voltages impressed at that particular instant upon the grids of the marking and spacing output amplifier tubes 1 and 12.
  • a center tap 15 connects the mid-point I 1 between the resistances l3 and M with an electronic tube It, which-in this particular form of the invention is a triode.
  • the tube. it ⁇ serves to detect the instantaneous value of the average of the noise currents in the marking and spacing paths.
  • the value of the voltage at the mid-point l1 follows closely therise in telegraph'distortion caused bynoise currents, it provides a means for detecting the existence of high distortion conditions due to poor mark-spacediscrimination. -'It also provides means for detecting the instantaneous value of the average of the noise currents in the marking and spacing paths of a signaling channel.
  • the detecting function of tube i8 is not directly responsive to the signalto-noise ratio, since an increase in the voltage at the mid-point l1 represents by itself a change inthesignal-to-noise ratio.
  • 1 which is the center tap of the 'resistanceconstituted by the resistance elements 2 l4 and 2 l 5, connects the junction' point 2
  • each amplifier tube is supplied from a. battery and through 'a resistance which is common to' and in series with the supply circuit for the screen grid of the corresponding output amplifier tube in the other channel.
  • a center tapped resistance comprising the equal series resistors 42'! and 428 is bridged across the control grids of tubes 42! and 422 in channel A and has its mid-point connected to the control grid of a triode 429.
  • a similar center tapped resistance comprising the equal series resistors 430 and 43] is bridged across the control grids of ,tubes 423 and 424 in channel B and has its midpoint connectedto the control grid of a triode 432.
  • the plate circuit of tube 429 includes the operating Winding of the cut-off relay 434, the nonoperating Winding of the cut-off relay 435 and the battery 433.
  • the plate of the marking output amplifier tube 421 in channel A is connected through the resistance 438 to battery 450 and the supply circuit for the screen grid of the marking output amplifier tube 423 in channel B extends along the conductor 439 and through the common series resistance 438 to battery-450.
  • extends along conductor 440 and through the resistance 44! to battery 450 and the plate of tube 423 in channel B is connected through the common series resistance 44! to battery 450.
  • the spacing output amplifier tubes 422 and 424 in channels A and B have their plates and screen grids similarly supplied from battery 450 through the common series resistances 442 and 443.
  • a diversity radio receiving system having at least two diversity receiving circuits for receiving signals, each of said diversity receiving circuits having detecting means for detecting noise currents in each circuit separately, and control means for reducing the gain in a noisy diversity receiving circuit and for correspondingly increasing the gain in another diversity receiving circuit in' response to the detection of noise currents by said detecting means, said control means including a plurality of electronic tubes connected in each diversity receiving circuit, each of said tubes having a plurality of electrodes, and coupling means for coupling an electrode of at least one tube in each circuit with an electrode of at least a one tube in the other diversity receiving circuit.
  • a diversity radio receiving system including at least two signal receiving channels, a plurality of current limiters, each of said current limiters being connected into a different channel, detecting means for separately detecting noise currents in each channel, said detecting mean including at least two equal seriesaconnected resistances bridged across each channel at a point subsequent to the current limiter in each channel, disabling means for selectively disabling said channels, and operating means for operating the disabling means to disable all but at least one of the channels in accordancewith the detection of noise currents by said detecting means.
  • a diversity radio receiving system having a plurality of signal receiving channels, each of said channels having detecting means for deriv ing a voltage representative of excessive noise currents present in that channel, cut-ofl means for cutting off said channels individually, said cut-01f means comprising a plurality of differential relays each having a plurality of windings, and operating means for separately applying said voltages to different windings of each of said relays for selectively operating said relays.
  • a dual diversity radio receiving system com,- prising two signal receiving channels, each of said channels having detecting means for deriving a voltage representative of the instantaneous value of excessive noise currents in that channel, cut- 011" means for cutting off said channels-alternatively said cut-off means comprising two differential relays each having a plurality of windings, and circuit means for differentially applying said voltages to two windings of each of said relays for operating said relays alternatively in accordance with the instantaneous noise conditions in the signal receiving channels.
  • a dual diversity radio receiving system comprising two signal receiving channels, each of said channels including at least one electronic amplifier, each of said amplifiers having at least one electrode, a current supply circuit extending to each of said electrodes, each of said channels having detecting means for deriving a voltage representative of the instantaneous value of excessive noise currents in that channel, disabling means for cutting ofi" said current supply circuit from said electrodes alternatively for disabling said amplifiers alternatively in accordance with the instantaneous noise conditions in the signal receiving channels, and operating means for differentially applying said voltages to the disabling means for operating said disabling means.
  • a diversity radio receiving system having a plurality of signal receiving channels, a receiving relay having an operating winding, means for combining the currents in said channels and for supplying said combined currents to the winding of the receiving relay, each of said channels having detecting means for deriving a voltage representative of the instantaneous value of excessive noise currents present in that channel, regulating means for regulating the currents in the channels for stabilizing their combined value at an approximately constant amount, and operating means for applying said voltages to the regulating means for operating said regulating means in accordance with the instantaneous noise conditions in the signal receiving channels.
  • a diversity radio receiving system comprisng in combination a plurality of signal receiving channels, each of said channels including-at least one variable gain amplifien; a receiving relay having an operating winaing,; means;ior combining the currents iii-said cna l elstand for supplying i c me edc r nts toxthe windin 01 n receivin re ay, each 9 s id.- nen vi detecting, mea s .e r vi s :13 vol a e rep tative or theinstantaneous value or noise currents present in that channel, control means ior reducing the gain o1';,tl 1e ;an 1pl n er 1n a .noisy channel and Ior, correspondingly increasing the gain or the amplifier -ln;.anotner channel 101 stabilizing their co nbined outputgcurrents at an approximatelyconstant amount, and operating means for applying said voltages to
  • regulating means comprising a pluranty or multielectrode electronic tubes, and operating means lor applying the voltage derived in one or said channels to an electrode 01 at least a first one or said tubes and Ior applying the voltage derlveu. in another or said channels to an electrode or at least a second one 01 said tubes Ior controlling the current now in said tubes in accordance with the instantaneous noise conditions in said channels.
  • a diversity radio receiving system comprising in combination a plurality of signal receiving channels, each of said channels including at least one variable gain multielectrode electronic ampliiier and detecting means for deriving a voltage representative of the instantaneous value of excessive noise current present in that channel, regulating means for reducing the gain of the amplifier in a channel in which excessive noise currents are present and for correspondingly increasing the gain of the amplifier in another of said channels, said regulating means comprising a plurality of multielectrode electronic tubes, operating means for applying the voltage derived in one of said channels to an electrode of at least a first one of said tubes and for applying the voltage derived in another of said channels to an electrode of at least a second one of said tubes for controlling the current flow in said tubes in accordance with the instantaneous noise conditions in said channels, and control means for connecting another electrode of said first one of said tubes to an electrode of one of said amplifiers and for connecting another electrode of said second one of said tubes to an electrode of another of said amplifiers.
  • a dual diversity radio telegraph receiving system comprising two signal receiving channels for receiving marking and spacing signals having different frequencies, each of said channels having a first band-pass filter for passing only waves of the marking frequency and a second bandpass filter for passing only waves of the spacin frequency, each of said channels also having a marking output amplifier tube with a control grid and a screen grid. and a spacing output amp ifi r tub With a cont elgrid a d? s en d.
  • a diversity radio receiving system comprising at least two signal receiving channels, each 01 said channels including at least one output amplifier tube having a screen grid, each of said screen grids having a voltage supply circuit, regulating means for reducing the gain of at least one output amplifier tube in one channel and for correspondingly increasing by an equal amount the gain of at least one output amplifier tube in another channel, said regulating means comprising control means for decreasing the voltage supplied to the screen grid of said tube in said first channel and for correspondingly increasing by an equal amount the voltage supplied to the screen grid of said tube in said second channel, said control means including resistors connected in said screen grid voltage supply circuits.
  • saidcompensating means including a, mat, commonseriesmeslstance ccnnected in the voltage-supply circuits forkhe anodeof at leash-one output amplifie-r tube in one channel audio!- the screen g-rid at at.

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  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Physics & Mathematics (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Measurement Of Current Or Voltage (AREA)
  • Radio Transmission System (AREA)
US536925A 1944-05-23 1944-05-23 Radio receiving system Expired - Lifetime US2384456A (en)

Priority Applications (6)

Application Number Priority Date Filing Date Title
BE481301D BE481301A (en(2012)) 1944-05-23
NL79786D NL79786C (en(2012)) 1944-05-23
FR959580D FR959580A (en(2012)) 1944-05-23
US536925A US2384456A (en) 1944-05-23 1944-05-23 Radio receiving system
GB20989/47A GB635590A (en) 1944-05-23 1947-08-01 Radio receiving systems
CH265990D CH265990A (de) 1944-05-23 1948-01-24 Radioempfangsanlage.

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US536925A US2384456A (en) 1944-05-23 1944-05-23 Radio receiving system

Publications (1)

Publication Number Publication Date
US2384456A true US2384456A (en) 1945-09-11

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Family Applications (1)

Application Number Title Priority Date Filing Date
US536925A Expired - Lifetime US2384456A (en) 1944-05-23 1944-05-23 Radio receiving system

Country Status (6)

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US (1) US2384456A (en(2012))
BE (1) BE481301A (en(2012))
CH (1) CH265990A (en(2012))
FR (1) FR959580A (en(2012))
GB (1) GB635590A (en(2012))
NL (1) NL79786C (en(2012))

Cited By (27)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2421054A (en) * 1945-06-15 1947-05-27 Press Wireless Inc Carrier-shift signal control circuits
US2488193A (en) * 1946-05-13 1949-11-15 Pye Ltd Radio communication system
US2495826A (en) * 1946-09-18 1950-01-31 Rca Corp Locking and control circuit in a diversity telegraphy receiver
US2497859A (en) * 1947-11-19 1950-02-21 Western Union Telegraph Co Frequency diversity telegraph system
US2507160A (en) * 1944-06-16 1950-05-09 Hartford Nat Bank & Trust Co Diversity receiving system
US2509212A (en) * 1946-02-05 1950-05-30 Int Standard Electric Corp Frequency shift radio telegraph system
US2512462A (en) * 1946-02-20 1950-06-20 Rca Corp Diversity system
US2514162A (en) * 1947-04-25 1950-07-04 Rca Corp Diversity reception
US2515055A (en) * 1946-05-31 1950-07-11 Rca Corp Diversity receiver
US2515668A (en) * 1945-12-05 1950-07-18 Rca Corp Gating circuit for diversity receivers
US2520308A (en) * 1947-02-20 1950-08-29 Erco Radio Lab Inc Frequency shift converter
US2543256A (en) * 1948-05-20 1951-02-27 Rca Corp Diversity receiver for multiplex frequency shift tones
US2553271A (en) * 1945-12-11 1951-05-15 Rca Corp Diversity receiver
US2555557A (en) * 1947-02-25 1951-06-05 Rca Corp Diversity receiver
US2568408A (en) * 1947-05-17 1951-09-18 Rca Corp Frequency shift diversity transmission system
US2589662A (en) * 1946-04-23 1952-03-18 Bell Telephone Labor Inc Radiotelephone receiving system
US2604587A (en) * 1947-11-12 1952-07-22 Rca Corp Signal selecting means
US2619587A (en) * 1949-07-23 1952-11-25 Rca Corp Diversity receiving system
US2648765A (en) * 1949-05-20 1953-08-11 Bell Telephone Labor Inc Noise detection circuit
US2694140A (en) * 1951-11-24 1954-11-09 Bell Telephone Labor Inc Selection of low interference radio channels
US2694141A (en) * 1951-12-22 1954-11-09 Bell Telephone Labor Inc Radiant energy signaling system
US2785301A (en) * 1946-03-05 1957-03-12 La Verne R Philpott Diversity amplification for superheterodyne receivers
US2835800A (en) * 1955-11-14 1958-05-20 James R Day Diversity receiving system
US2835799A (en) * 1955-06-24 1958-05-20 James R Day Diversity receiving system
US2841701A (en) * 1948-12-03 1958-07-01 Int Standard Electric Corp Diversity radio telegraph system
US2899548A (en) * 1955-04-22 1959-08-11 channel
US3026455A (en) * 1959-07-02 1962-03-20 Philco Corp Differential switching amplifier

Cited By (27)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2507160A (en) * 1944-06-16 1950-05-09 Hartford Nat Bank & Trust Co Diversity receiving system
US2421054A (en) * 1945-06-15 1947-05-27 Press Wireless Inc Carrier-shift signal control circuits
US2515668A (en) * 1945-12-05 1950-07-18 Rca Corp Gating circuit for diversity receivers
US2553271A (en) * 1945-12-11 1951-05-15 Rca Corp Diversity receiver
US2509212A (en) * 1946-02-05 1950-05-30 Int Standard Electric Corp Frequency shift radio telegraph system
US2512462A (en) * 1946-02-20 1950-06-20 Rca Corp Diversity system
US2785301A (en) * 1946-03-05 1957-03-12 La Verne R Philpott Diversity amplification for superheterodyne receivers
US2589662A (en) * 1946-04-23 1952-03-18 Bell Telephone Labor Inc Radiotelephone receiving system
US2488193A (en) * 1946-05-13 1949-11-15 Pye Ltd Radio communication system
US2515055A (en) * 1946-05-31 1950-07-11 Rca Corp Diversity receiver
US2495826A (en) * 1946-09-18 1950-01-31 Rca Corp Locking and control circuit in a diversity telegraphy receiver
US2520308A (en) * 1947-02-20 1950-08-29 Erco Radio Lab Inc Frequency shift converter
US2555557A (en) * 1947-02-25 1951-06-05 Rca Corp Diversity receiver
US2514162A (en) * 1947-04-25 1950-07-04 Rca Corp Diversity reception
US2568408A (en) * 1947-05-17 1951-09-18 Rca Corp Frequency shift diversity transmission system
US2604587A (en) * 1947-11-12 1952-07-22 Rca Corp Signal selecting means
US2497859A (en) * 1947-11-19 1950-02-21 Western Union Telegraph Co Frequency diversity telegraph system
US2543256A (en) * 1948-05-20 1951-02-27 Rca Corp Diversity receiver for multiplex frequency shift tones
US2841701A (en) * 1948-12-03 1958-07-01 Int Standard Electric Corp Diversity radio telegraph system
US2648765A (en) * 1949-05-20 1953-08-11 Bell Telephone Labor Inc Noise detection circuit
US2619587A (en) * 1949-07-23 1952-11-25 Rca Corp Diversity receiving system
US2694140A (en) * 1951-11-24 1954-11-09 Bell Telephone Labor Inc Selection of low interference radio channels
US2694141A (en) * 1951-12-22 1954-11-09 Bell Telephone Labor Inc Radiant energy signaling system
US2899548A (en) * 1955-04-22 1959-08-11 channel
US2835799A (en) * 1955-06-24 1958-05-20 James R Day Diversity receiving system
US2835800A (en) * 1955-11-14 1958-05-20 James R Day Diversity receiving system
US3026455A (en) * 1959-07-02 1962-03-20 Philco Corp Differential switching amplifier

Also Published As

Publication number Publication date
FR959580A (en(2012)) 1950-03-31
NL79786C (en(2012))
CH265990A (de) 1949-12-31
GB635590A (en) 1950-04-12
BE481301A (en(2012))

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