GB1123416A - Telegraph receiving apparatus - Google Patents
Telegraph receiving apparatusInfo
- Publication number
- GB1123416A GB1123416A GB4926165A GB4926165A GB1123416A GB 1123416 A GB1123416 A GB 1123416A GB 4926165 A GB4926165 A GB 4926165A GB 4926165 A GB4926165 A GB 4926165A GB 1123416 A GB1123416 A GB 1123416A
- Authority
- GB
- United Kingdom
- Prior art keywords
- channel
- hybrid transformer
- hybrid
- mixer
- mixers
- 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
- 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
Abstract
1,123,416. Radio receiving systems; telegraphy. STANDARD TELEPHONES & CABLES Ltd. 19 Nov., 1965, No. 49261/65. Headings H4L and H4P. In an alternating-current telegraph receiver including two separate signal paths, the said paths are coupled to a common impedance by a hybrid circuit arrangement so arranged that substantially no power is transferred from either path to the other. As described, the output A of a first receiving channel of a radio diversity system is connected through a band pass filter 1 to a hybrid transformer 4, by which it is divided to feed a mixer 8 in a "mark" channel 33 and a similar mixer 9 in a "space" channel 35. Similarly, the output B of a second receiving channel is divided by a hybrid transformer 11 to feed a mixer 15 in a "mark" channel 34 and a similar mixer 16 in a "space" channel 36. A common local oscillator 17 is coupled by a hybrid transformer 19 to the mixers 8, 15 and a common local oscillator 18 is coupled by a hybrid transformer 24 to the mixers 9, 16. In the hybrid transformer 4, the value of the balancing resistor 7 is so chosen in relation to the input impedance associated with the primary winding 3 and the turns ratio between the secondary 5, 6 and the primary, that there is substantially no cross-coupling between the mixers 8 and 9. Similar considerations are applied to the other hybrid transformers 11, 19, 24. With a frequency shift keying system, the input carrier frequency may be 100 kc/s, with Œ0À1 kc/s shift, the oscillators 17, 18 being set, respectively, at 94À9 kc/s and 95À1 kc/s, so that the "mark" and "space" outputs are all at 5 kc/s. The arrangement may be extended for use in a frequency-shift diplex system, where four frequencies deviated from a carrier are used, or it may be adapted for on-off keying, when the oscillator 18 would be disabled. With a non-diversity system only one hybrid transformer, 4 or 11 would be used.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB4926165A GB1123416A (en) | 1965-11-19 | 1965-11-19 | Telegraph receiving apparatus |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB4926165A GB1123416A (en) | 1965-11-19 | 1965-11-19 | Telegraph receiving apparatus |
Publications (1)
Publication Number | Publication Date |
---|---|
GB1123416A true GB1123416A (en) | 1968-08-14 |
Family
ID=10451728
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB4926165A Expired GB1123416A (en) | 1965-11-19 | 1965-11-19 | Telegraph receiving apparatus |
Country Status (1)
Country | Link |
---|---|
GB (1) | GB1123416A (en) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4549185A (en) * | 1981-11-03 | 1985-10-22 | Amstar Technical Products Co., Inc. | Signal distribution system |
WO2013063506A3 (en) * | 2011-10-26 | 2013-08-22 | Qualcomm Incorporated | Impedance balancing for transmitter to receiver rejection |
US8843081B2 (en) | 2011-05-16 | 2014-09-23 | Qualcomm Incorporated | Receiver with transmit signal cancellation |
US8971219B2 (en) | 2012-03-30 | 2015-03-03 | Qualcomm Incorporated | Hybrid transformer based integrated duplexer for multi-band/multi-mode radio frequency (RF) front end |
US9118396B2 (en) | 2012-03-30 | 2015-08-25 | Qualcomm Incorporated | Tunable notch filter using feedback through an existing feedback receiver |
-
1965
- 1965-11-19 GB GB4926165A patent/GB1123416A/en not_active Expired
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4549185A (en) * | 1981-11-03 | 1985-10-22 | Amstar Technical Products Co., Inc. | Signal distribution system |
US8843081B2 (en) | 2011-05-16 | 2014-09-23 | Qualcomm Incorporated | Receiver with transmit signal cancellation |
WO2013063506A3 (en) * | 2011-10-26 | 2013-08-22 | Qualcomm Incorporated | Impedance balancing for transmitter to receiver rejection |
US9083441B2 (en) | 2011-10-26 | 2015-07-14 | Qualcomm Incorporated | Impedance balancing for transmitter to receiver rejection |
US8971219B2 (en) | 2012-03-30 | 2015-03-03 | Qualcomm Incorporated | Hybrid transformer based integrated duplexer for multi-band/multi-mode radio frequency (RF) front end |
US9118396B2 (en) | 2012-03-30 | 2015-08-25 | Qualcomm Incorporated | Tunable notch filter using feedback through an existing feedback receiver |
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