US2416328A - Radio receiver - Google Patents

Radio receiver Download PDF

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Publication number
US2416328A
US2416328A US449595A US44959542A US2416328A US 2416328 A US2416328 A US 2416328A US 449595 A US449595 A US 449595A US 44959542 A US44959542 A US 44959542A US 2416328 A US2416328 A US 2416328A
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US
United States
Prior art keywords
impulses
time
constant
harmonic
duration
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
US449595A
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English (en)
Inventor
Labin Emile
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
Federal Telephone and Radio Corp
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
Priority to BE479581D priority Critical patent/BE479581A/xx
Priority to FR954515D priority patent/FR954515A/fr
Application filed by Standard Telephone and Cables PLC filed Critical Standard Telephone and Cables PLC
Priority to US449595A priority patent/US2416328A/en
Priority to GB8847/44A priority patent/GB593731A/en
Application granted granted Critical
Publication of US2416328A publication Critical patent/US2416328A/en
Priority to ES0182235A priority patent/ES182235A1/es
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03K—PULSE TECHNIQUE
    • H03K9/00—Demodulating pulses which have been modulated with a continuously-variable signal
    • H03K9/04—Demodulating pulses which have been modulated with a continuously-variable signal of position-modulated pulses

Definitions

  • This invention relates to. receiverv systems and more particularly to timemodulated impulse re,- DCvers;
  • a receiver may then be used in which is provided a selective circuit tuned substantially to a harmonic of the period.
  • the harmonic is s pulses of a. pair at one extreme position of modulation, such as at the constant ⁇ Vtiming limit of the ⁇ successive impulses, is an odd number of half wavelengths whereupon zero ⁇ energy is passed" by the filter.
  • the interval spacing between impulses oifA a pair is such that considerable energy'is passed' by the lter.
  • energy4v at a level intermediate'the two extremes passes the lter.
  • the ⁇ i objects are accomplished; byt providing means for regenerating or reshaping thezreceivedimpul'sesf before' passing? the: energyv through; a selective@ band-pass filter; 'Ihisis ⁇ done-.byusingthe re.- ceived4 impulse to ⁇ initiate; a new pulse withq-.oneedge thereof, and this new pulse is made of whatsoever-l determined 'durationfindepend'ent of the signal level.
  • the new impulses are preferably made of aI predetermined substantiallyv constant:Y
  • Fig. 2 is a block diagram of a simplified receive'rf' made in accordance with myinventiomiand
  • Fig. 3 shows a more detailed circuit diagram-1 of a simpleform of shaping circuit inl accordance with my invention.
  • y f i v Turning iivrstto' Fig'. 1 a brief explanation of* the operation of the transmitter system describedf more fully in my abovevreierr'ed' to application, ⁇
  • the signal may be translated by the use of a properly chosen harmonic frequency.
  • vIt is, therefore, possible with this type of system to receive the signals fby means of a sharply tuned filter which will pass only the particular related harmonics and the modulation signals immediately adjacent thereto.
  • how-v ever, ⁇ a relatively high' harmonic is preferably used'in order that the energy level may change substantially for slight impulse displacement;
  • the amount of energy of such high harmonic in the received signal is relatively feeble and accordingly requires a more sensitive amplifier than is required to detect'the entire impulse. Accordingly, I provide means for reshaping and enlarging the received impulses without' disturbing their normal spacingprior to the harmonic selection so that stronger signal indications may be ob- ⁇ tained.
  • each of the; impulses la to 6a inclusive as they areY received causes the shaping circuit to be moved into operative position.
  • the circuit then preferably re'- ⁇ mains in this operative position for a predetermined length of/time when it again returns to normal unoperated position, thus producing square wave impulses such as shown at Ib, 2b, etcQ o1' curve B.
  • harmonic curve C is considfered, impulses I and 2 will produce the impulses Ib and 2b which intersect the portions Ic and 2c of harmonic curveC.
  • impulses Ib and 2b intersect parts Ic and 2c of equalY length and opposite-sign-so that at the receiverthezero indication is obtained.
  • Impulses 3b and 4b are similarly positioned to intercept portion 3c and 4c of curve C.
  • square wave 517-61) vwilll beproduced which intercept the portions 5c--6c of curve C.
  • the impulses will be positioned midway between those shown circuit in accordancewith my invention.
  • incoming high frequency impulses are impressed on the input of the radio frequency and intermediate frequency amplifier 2U.
  • This amplifier preferably includes la first detectingv means in order'that extremely high radio frequencies may be reduced to a lower value. If .the impulses are also amplitude modulated to convey a further message, these amplitude modulating signals may be detected in an amplitude detector 22. and impressed on ⁇ earphones 23 or with proper amplification on to any form of sound Itranslater.
  • the time modulated impulses are passed" from amplifier 20 to a clipper amplitude limiter 2I.
  • VSuch a limiter serves to clip off the lower part of the 'impulses where they tend to trail out reducing noise effectsand to'limit the amplitudes of the pulses to a constant level.
  • the clipping eiect is the more importantof the two so far as reduction of noise level is concerned.
  • This amplitude limiter is especially desirable if the impulses have been amplitudemodulated but is often desirable in any case since itrmay serve to cut off theparts of the impulses where the greatest-noise level may be present. ⁇
  • the limited impulses are .then passed on to a shaping circuit 24 which imparts to these 'im-r pulses the rgeneral form'shown in curve B ofl Fig. 1.
  • VThis shaping circuit will be described in rmore detail later, vIn order that impulses Ib, 2b,
  • the limiter may be omitted, in which case thek is clear, however, that with suitable amplification any type of translator may be used.
  • Impulses Ib, 2b, etc. are preferably'made suflll ciently wide to encompass substantially the entire scope of signals la and 2 a, so that thel Yending of the square waves ls not iniluenced bythe trail-lf, ing ends of the incoming pulses.. If this is not;
  • the abovefeature has the veryimportant gid/g., vantage of substantially reducing :the: noise-tof.)
  • the present invention eliminates that part of the noise effect due to variations in the width of lthe pulses.
  • impulses such as shown at la and 2a, etc. of Fig. 1 are generally much steeper on their leading edges and tend to trail oii on their trailing edges. For this reason the shaping network if controlled by the leading edges (as is preferred) tends to further reduce the noise-tosignal ratio which might otherwise exist. If, for any reason, control by the trailing edge is desired, the impulses may be passed through a differentiating circuit and a clipper before application to the multivibrator.
  • The'time constant of the circuit including condenser 33 and resistor 34 determines the duration of the operative condition of the shaping circuit 24 and asa consequence the duration of a pulse. This time constant may be changed by adjusting resistor 3! to the de@ sired value.
  • the adjustment 'of resistor 30 may serve to vary the cut-01T points of the tubes VI and V2 and thus to adjust the duration of the impulse without changing the time constants of circuits t3. 3i;
  • the square wave impulses pro-'f cuted in this multivibrator'circuit 24 are taken oi' across grid cathode resistor 35 and applied'to the input of the band-pass filter 26 of Fig. 2.
  • shaping circuits may be designed than the simple multivibratorI circuit shown herein.
  • the prime requisites of my' invention aretnat the shaping networkV be ⁇ such that it will be brought into operation by one of the edges of the received impulses and will be made ⁇ to continue in operation for a period of substantially iixed length.
  • a receiving circuit shown in Fig. 2 mayk be provided with other apparatus for blocking out all signals between the times when the impulses are to be received as disclosed in my above referred copending application.
  • a receiver for detecting time modulated impulse energy wherein the impulses are modulated by pairs at least one of the pulses of each pair being time displaced relative to the other between two limits according to the instantaneous value of the modulating signal, one of such limits being defined by a constant timing interval; said receiver comprising means for shaping the received impulses into substantially constant duration impulses, filter means passing substantially only a band of frequencies immediately about a harmonic of said constant timing interval, whereby energy of said constant duration impulses is passed according to the time displacement thereof from one of said limits, and means to detect the energy passed by said lter means.
  • a receiver according to claim 1 wherein said shaping means comprises means triggered by the leading edge of each of said received impulses for producing said constant duration impulses.
  • a receiver comprises means triggered by the leading edge of each of said received impulses for producing said constant duration impulses and means for limiting the impulses to a subtion in one direction by the leading edge of each i received impulse and to return to said normal condition a predetermined time after movement in said one direction.
  • a receiver according to claim 1 wherein the shaping means is adjustable for obtaining output impulses of a duration equal to a half periodi of the harmonic of said constant timing-interval.
  • a receiver for segregating and detecting time modulated impulse energy wherein 'the impulses are modulated bypairs at least one of the pulses of each pair being time displaced relative to the other between two limits according to the instantaneous value of the modulating signal, one of such limits being characterized by a constant timing with respect to pulse pairs; said receiver comprising amplitude limiting means for limiting the received impulses to' a predetermined level to remove any amplitude modulation effects therefrom, means for shaping the amplitude limited impulses into substantially constant duration im- Y pulses, and lter means passing substantially only a band of frequencies close about a harmonic-of said constant timing characteristic of the pulse pairs 'whereby energy of said constant duration impulsesis passed according to the time displace- 'ment thereof from one of said limits, and means being time displaced relative to the other between two limits according to the instantaneous value of the Vmodulating signal, one of such limits be ceived impulse.
  • duration of said constant duration -impulsesis- ⁇ 10 8. The method defined in claim 7 wherein duration of said constant duration -impulsesis- ⁇ 10.
  • the method defined in claim 7whereinvthev shaping operation is characterized by timing the; leading edges of each constant duration impulse with the leading edge of the corresponding received impulses, and the duration of said constant duration impulses is selected equal to a half peri od of said harmonic.

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  • Dc Digital Transmission (AREA)
  • Professional, Industrial, Or Sporting Protective Garments (AREA)
  • Electrotherapy Devices (AREA)
  • Burglar Alarm Systems (AREA)
  • Noise Elimination (AREA)
US449595A 1942-07-03 1942-07-03 Radio receiver Expired - Lifetime US2416328A (en)

Priority Applications (5)

Application Number Priority Date Filing Date Title
BE479581D BE479581A (xx) 1942-07-03
FR954515D FR954515A (xx) 1942-07-03
US449595A US2416328A (en) 1942-07-03 1942-07-03 Radio receiver
GB8847/44A GB593731A (en) 1942-07-03 1944-05-09 Receivers for pulse communication systems
ES0182235A ES182235A1 (es) 1942-07-03 1948-02-10 Mejora en radiorreceptores

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US449595A US2416328A (en) 1942-07-03 1942-07-03 Radio receiver

Publications (1)

Publication Number Publication Date
US2416328A true US2416328A (en) 1947-02-25

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ID=23784755

Family Applications (1)

Application Number Title Priority Date Filing Date
US449595A Expired - Lifetime US2416328A (en) 1942-07-03 1942-07-03 Radio receiver

Country Status (5)

Country Link
US (1) US2416328A (xx)
BE (1) BE479581A (xx)
ES (1) ES182235A1 (xx)
FR (1) FR954515A (xx)
GB (1) GB593731A (xx)

Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2456026A (en) * 1947-06-14 1948-12-14 Rca Corp Modulator employing trigger circuit
US2467308A (en) * 1945-03-17 1949-04-12 Rca Corp Interference reducing radio pulse receiver
US2467793A (en) * 1945-05-19 1949-04-19 Westinghouse Electric Corp Radio communication system
US2474244A (en) * 1944-05-19 1949-06-28 Standard Telephones Cables Ltd Amplitude modulated time modulated pulse system
US2480171A (en) * 1943-02-18 1949-08-30 Sperry Corp Pulse receiver system for improved target tracking
US2498675A (en) * 1943-05-24 1950-02-28 Standard Telephones Cables Ltd Radio receiver
US2507351A (en) * 1945-11-23 1950-05-09 Well Surveys Inc Transmitting of information in drill holes
US2509064A (en) * 1945-08-23 1950-05-23 Bell Telephone Labor Inc Reduction of noise in pulse position modulation systems
US2525634A (en) * 1945-12-07 1950-10-10 Rca Corp Pulse communication system
US2561612A (en) * 1945-05-10 1951-07-24 Honeywell Regulator Co Cathode-ray tube apparatus for comparing two electrical signals
US2573354A (en) * 1945-07-26 1951-10-30 Rca Corp Variable frequency multivibrator
US2578557A (en) * 1946-01-25 1951-12-11 Rca Corp Electric timing device
US2597029A (en) * 1946-09-21 1952-05-20 Int Standard Electric Corp Superheterodyne radio receiver employing a multifunction tube
US2604608A (en) * 1942-11-28 1952-07-22 James R Moore Time wave generating system
US2605460A (en) * 1944-09-20 1952-07-29 Howard C Storck Suppression system
US2623173A (en) * 1947-06-05 1952-12-23 Gen Teleradio Inc Television phase-actuated control equipment
US2623994A (en) * 1947-02-17 1952-12-30 Patelhold Patentverwertung Receiver for time modulated pulses
US2662174A (en) * 1942-11-25 1953-12-08 Hartford Nat Bank & Trust Co Amplitude discriminating noise reducing means
US2740043A (en) * 1952-03-03 1956-03-27 John E Williams Electronic linear sweep generator

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2113214A (en) * 1936-10-29 1938-04-05 Rca Corp Method of frequency or phase modulation
US2266526A (en) * 1938-04-11 1941-12-16 Emi Ltd Electrical oscillation generator

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2113214A (en) * 1936-10-29 1938-04-05 Rca Corp Method of frequency or phase modulation
US2266526A (en) * 1938-04-11 1941-12-16 Emi Ltd Electrical oscillation generator

Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2662174A (en) * 1942-11-25 1953-12-08 Hartford Nat Bank & Trust Co Amplitude discriminating noise reducing means
US2604608A (en) * 1942-11-28 1952-07-22 James R Moore Time wave generating system
US2480171A (en) * 1943-02-18 1949-08-30 Sperry Corp Pulse receiver system for improved target tracking
US2498675A (en) * 1943-05-24 1950-02-28 Standard Telephones Cables Ltd Radio receiver
US2474244A (en) * 1944-05-19 1949-06-28 Standard Telephones Cables Ltd Amplitude modulated time modulated pulse system
US2605460A (en) * 1944-09-20 1952-07-29 Howard C Storck Suppression system
US2467308A (en) * 1945-03-17 1949-04-12 Rca Corp Interference reducing radio pulse receiver
US2561612A (en) * 1945-05-10 1951-07-24 Honeywell Regulator Co Cathode-ray tube apparatus for comparing two electrical signals
US2467793A (en) * 1945-05-19 1949-04-19 Westinghouse Electric Corp Radio communication system
US2573354A (en) * 1945-07-26 1951-10-30 Rca Corp Variable frequency multivibrator
US2509064A (en) * 1945-08-23 1950-05-23 Bell Telephone Labor Inc Reduction of noise in pulse position modulation systems
US2507351A (en) * 1945-11-23 1950-05-09 Well Surveys Inc Transmitting of information in drill holes
US2525634A (en) * 1945-12-07 1950-10-10 Rca Corp Pulse communication system
US2578557A (en) * 1946-01-25 1951-12-11 Rca Corp Electric timing device
US2597029A (en) * 1946-09-21 1952-05-20 Int Standard Electric Corp Superheterodyne radio receiver employing a multifunction tube
US2623994A (en) * 1947-02-17 1952-12-30 Patelhold Patentverwertung Receiver for time modulated pulses
US2623173A (en) * 1947-06-05 1952-12-23 Gen Teleradio Inc Television phase-actuated control equipment
US2456026A (en) * 1947-06-14 1948-12-14 Rca Corp Modulator employing trigger circuit
US2740043A (en) * 1952-03-03 1956-03-27 John E Williams Electronic linear sweep generator

Also Published As

Publication number Publication date
GB593731A (en) 1947-10-23
BE479581A (xx)
FR954515A (xx) 1950-01-03
ES182235A1 (es) 1948-04-01

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