GB675382A - Improvements in and relating to interference reduction circuits - Google Patents
Improvements in and relating to interference reduction circuitsInfo
- Publication number
- GB675382A GB675382A GB1314/50A GB131450A GB675382A GB 675382 A GB675382 A GB 675382A GB 1314/50 A GB1314/50 A GB 1314/50A GB 131450 A GB131450 A GB 131450A GB 675382 A GB675382 A GB 675382A
- Authority
- GB
- United Kingdom
- Prior art keywords
- frequency
- modulation
- interference
- carrier
- phase
- 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
Links
Classifications
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03D—DEMODULATION OR TRANSFERENCE OF MODULATION FROM ONE CARRIER TO ANOTHER
- H03D5/00—Circuits for demodulating amplitude-modulated or angle-modulated oscillations at will
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Noise Elimination (AREA)
Abstract
675,382. Radio receiving systems; frequency modulation. BRITISH THOMSON-HOUSTON CO., Ltd. Jan. 18, 1950 [Jan. 25, 1949], No. 1314/50. Class 40 (v). In an A.M. or F.M. receiver the frequency modulation and amplitude modulation of the carrier wave due to interference are both detected and one used to balance out the other. The signal detector or discriminator has in parallel a discriminator or detector circuit for detecting carrier modulation, due to interference, of opposite type to the signal modulation and comprising a differentiating circuit 5, 6 (in an F.M. receiver, as shown) or integrating circuit (in an A.M. receiver, Fig. 3, not shown) and amplifier 7 so that the interference varies equally in amplitude with that in the main circuit as the frequency α varies, where α is the difference in frequency between the carrier and the interfering wave or between the carrier and the noise induced side-bands, respectively. Further the main and auxiliary circuits include phase shifters 8, 9 producing phase shifts of # and # + 90 degrees of constant phase difference compensating the 90 degree phase shift due to the differentiating or integrating circuit, so that the interference voltages are of phase to balance out. To this end the phase shifters 8, 9 may be of the type producing phase shift proportional to the logarithm of the frequency α of the input.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US675382XA | 1949-01-25 | 1949-01-25 |
Publications (1)
Publication Number | Publication Date |
---|---|
GB675382A true GB675382A (en) | 1952-07-09 |
Family
ID=22076669
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB1314/50A Expired GB675382A (en) | 1949-01-25 | 1950-01-18 | Improvements in and relating to interference reduction circuits |
Country Status (1)
Country | Link |
---|---|
GB (1) | GB675382A (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE3247428A1 (en) * | 1982-12-22 | 1984-06-28 | Blaupunkt-Werke Gmbh, 3200 Hildesheim | Method of suppressing inferences induced by two-way propagation and circuit arrangement for this purpose |
-
1950
- 1950-01-18 GB GB1314/50A patent/GB675382A/en not_active Expired
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE3247428A1 (en) * | 1982-12-22 | 1984-06-28 | Blaupunkt-Werke Gmbh, 3200 Hildesheim | Method of suppressing inferences induced by two-way propagation and circuit arrangement for this purpose |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
GB1338201A (en) | Signal processor for reception of amplitude or frequency modulated signals | |
GB1059393A (en) | Improvements in or relating to demodulators for frequency modulated waves | |
GB489636A (en) | Carrier wave transmission systems | |
GB675382A (en) | Improvements in and relating to interference reduction circuits | |
GB1295380A (en) | ||
GB1117475A (en) | Method of measuring frequency dependent group delay distortion | |
US2485582A (en) | Receiver system | |
GB610534A (en) | Improvements in radio distance measuring systems | |
GB792350A (en) | Improvements in or relating to single-sideband radio receivers | |
GB845847A (en) | Radio diversity receiving system | |
US3339143A (en) | Selective receiver for communication by phase shift | |
US2605395A (en) | Noise suppression circuits | |
SU118081A1 (en) | Measuring receiver for ultra high frequencies | |
GB736281A (en) | Improved radio receiving equipment for omnidirectional phase beacon navigation systems | |
GB602488A (en) | Apparatus for receiving transmitted radio waves | |
GB626325A (en) | Receiving and indicating system for a variable-frequency rotary beacon | |
GB1533432A (en) | Fm tuner | |
GB1046806A (en) | Improvement in wide-band discriminators | |
GB898496A (en) | Improvements in or relating to speech-signal transmission systems | |
GB621803A (en) | Radio receiving system | |
GB911495A (en) | A reception system of high sensitivity for frequency or phase-modulated waves | |
GB1152854A (en) | Improvements in or relating to Distance Measuring Apparatus | |
GB783580A (en) | Improvements in or relating to automatic frequency control arrangements for frequency shift telegraph receivers | |
GB1179032A (en) | Improvements in Circuits for Detecting the Presence of Low Level Sinusoidal Electric Signals | |
GB639686A (en) | Improvements relating to tuning means for mixed radio receivers adapted for amplitude modulation or frequency modulation |