US6038238A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method to realize discontinuous transmission in a mobile phone system
Assignee: Nokia Solutions and Networks Oy
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Filing: 1997-07-29
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Granted: 2000-03-14
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Expires: 2017-07-29
Abstract
Abstract The object of the invention is a method to realize discontinuous transmission (DTX) in a telecommunications network, e.g. in a GSM (Global System for Mobile Communications) mobile phone network, particularly on the downlink. The disadvantage of known methods is that dummy bursts transmitted on the frequency of the broadcasting channel cause disturbing responses in a mobile phone, when frequency hopping is used. In the solution according to the invention the bursts transmitted on the frequency of the broadcasting channel are encoded so that after decoding the mobile phone prevents information contained in a dummy burst to be interpreted as speech. In this way the mobile phone responds with noise on the dummy bursts transmitted on the broadcasting frequency.
Inventors
- 👤 Harri Jokinen
- 👤 Hannu Pirila
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 08:33
CPC Classifications
H; H04; H04B; H04B7/00; H04B7/24; H04B7/26; H04B7/2615; H04W; H04W88/00; H04W88/08
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
157 words
A method to realize discontinuous transmission (DTX) in a mobile phone system, with a broadcasting channel (BCCH) and communication channels transmitting speech information, in the transmission of speech information from a base station to a mobile phone having receiver circuits, comprising the steps of: utilizing the broadcasting channel (BCCH) and the frequency of the broadcasting channel to carry the speech information transmissions of one or more communication channels by using frequency hopping, transmitting dummy bursts, comprising frames containing one or more blocks without speech information, on the frequency of the broadcasting channel, during the DTX state when speech information is not being transmitted, and during the DTX state, encoding a dummy burst that is transmitted on the frequency of the broadcasting channel in such a way that the receiver circuits of the mobile phone are controlled to process as bad frames the received frames which are read from the dummy burst and comprise one or more blocks.
Claim 2
Independent Claim
157 words
A method to realize discontinuous transmission (DTX) in a mobile phone system, with a broadcasting channel (BCCH) and communication channels transmitting speech information, in the transmission of speech information from a base station to a mobile phone having receiver circuits, comprising the steps of: utilizing the broadcasting channel (BCCH) and the frequency of the broadcasting channel to carry the speech information transmissions of one or more communication channels by using frequency hopping, transmitting dummy bursts, comprising frames containing one or more blocks without speech information, on the frequency of the broadcasting channel, during the DTX state when speech information is not being transmitted, and during the DTX state, encoding a dummy burst that is transmitted on the frequency of the broadcasting channel in such a way that the receiver circuits of the mobile phone are controlled to process as bad frames the received frames which are read from the dummy burst and comprise one or more blocks.
Claim 3
Dependent Claim
37 words
The method according to claim 1, characterized in that, during discontinuous transmission, one or more blocks of the frame of a dummy burst transmitted on the frequency of the broadcasting channel are encoded as a signaling block.
Claim 4
Dependent Claim
55 words
The method according to claim 1, characterized in that, during the DTX state, the second block in the frames of one or more bursts, which frames have a first block being a Silence Information Description (SID) block and which frames are transmitted on the frequency of the broadcasting channel, is encoded as a signaling block.
Claim 5
Dependent Claim
24 words
The method according to claim 2, characterized in that said encoding is made with the aid of a stealing bit in the transmitted block.
Claim 6
Dependent Claim
20 words
The method according to claim 4, characterized in that the stealing bit is given the value 1 in said encoding.
Claim 7
Dependent Claim
48 words
The method according to claim 1, characterized in that, during the DTX state, the dummy bursts transmitted on the frequency of the broadcasting channel use a training sequence comprising a bit stream which is different from the training sequences transmitted on the communication channels during the normal state.
Claim 8
Dependent Claim
66 words
The method according to claim 6, characterized in that the training sequence of the dummy bursts is selected so that a received frame is treated as a bad frame based on the result of a cross correlation determination made in the mobile phone, between on one hand the received training sequence and on the other hand one or more training sequences used in the normal state.
Claim 9
Dependent Claim
65 words
The method according to claim 6, characterized in that the training sequence of the dummy bursts is selected so that a received frame is treated as a bad frame based on the result of a cross correlation determination made in the mobile phone, between on one hand the received training sequence and on the other hand a training sequence made known to the mobile phone.
Claim 10
Dependent Claim
38 words
The method according to claim 6, characterized in that the bit stream used as the training sequence of the dummy burst is selected so that its cross correlation with one or more training sequences in use is minimized.
Claim 11
Dependent Claim
34 words
The method according to claim 6, characterized in that the bit sequence (0,1,1,1,0,0,0,1,0,1,1,1,0,0,0,1,0,1,1,1, 0,0,0,1,0,1) is used as the bit stream of the training sequence of the dummy burst transmitted on the broadcasting channel (BCCH).
Claim 12
Dependent Claim
64 words
The method according to claim 6, characterized in that the dummy burst transmitted in the DTX state on the frequency of the broadcasting channel utilizes a training sequence stored in the receiver circuits of a mobile phone, which is different from the training sequence used on a communication channel in the normal state, and the identity of which is transmitted to the mobile phone.
Claim 13
Dependent Claim
35 words
The method according to claim 11, characterized in that an encoding is performed on a burst by which the mobile phone is controlled to generate comfort noise as a response to the burst when received.
Claim 14
Dependent Claim
13 words
The use of the method according to claim 12 in the GSM system.
Claim 15
Dependent Claim
24 words
The method according to claim 3, characterized in that said encoding is made with the aid of a stealing bit in the transmitted block.
Claim 16
Dependent Claim
20 words
The method according to claim 14, characterized in that the stealing bit is given the value 1 in said encoding.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2003-03-14 | 2003-09-13 | 2004-03-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2007-03-14 | 2007-09-13 | 2008-03-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2011-03-14 | 2011-09-13 | 2012-03-14 | $7700.00 | Window Closed / Lapsed |