US5757810A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Transmission link supervision in radiocommunication systems
Assignee: Unwired Planet LLC
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Filing: 1995-11-24
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Granted: 1998-05-26
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Expires: 2015-11-24
Abstract
Abstract A digital cellular communications system has a bidirectional transmission link for conveying encoded speech and control data in the form of blocks, a switching unit coupled to a first end of the transmission link, and a base station coupled to a second end of the transmission link. The switching unit includes a speech encoder for encoding speech signals, an error detection code generator for generating an error detection code from the encoded speech signal, and a formatter, coupled to the error detection code generator, for producing a formatted block to be transmitted on the transmission link, the formatted block having a header, the encoded speech data, and the error detection code. The base station has a transmission link error detector for signalling the existence of an error in a received block in response to the received block containing an error. Similarly, the switching unit has a transmission link error detector for signalling the existence of an erroneously received block which has been transmitted in the uplink direction. The number of errors is monitored by a transmission link supervisor which reports if the errors indicate that the quality of the transmission link has degraded beyond a predetermined threshold.
Inventors
- 👤 Sven Orjan Patrik Fall
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 15:19
CPC Classifications
H; H04; H04W; H04W24/00; H04L; H04L1/00; H04L1/24
Claims Analysis
Total Claims: 33
Claim 1
Independent Claim
163 words
A digital cellular communications system comprising: a switching unit including a speech code for coding downlink speech signals and decoding uplink speech signals that are respectively transmitted to and received from a base station via a transmission link; wherein the transmission link conveys encoded downlink and uplink speech and control data in the form of respective downlink and uplink blocks; wherein the base station operates to relay an encoded downlink speech signal received from the switching unit to a mobile station by transmission on a radio channel and to relay to the switching unit an encoded uplink speech signal received from the mobile station by transmission on the transmission link; and means for marking a monitoring interval if a predetermined number of one of downlink and uplink blocks is conveyed erroneously over said transmission link during said monitoring interval and for reporting said transmission link as having poor quality if a predetermined number of monitoring intervals are marked within a predetermined time period.
Claim 2
Dependent Claim
163 words
A digital cellular communications system comprising: a switching unit including a speech code for coding downlink speech signals and decoding uplink speech signals that are respectively transmitted to and received from a base station via a transmission link; wherein the transmission link conveys encoded downlink and uplink speech and control data in the form of respective downlink and uplink blocks; wherein the base station operates to relay an encoded downlink speech signal received from the switching unit to a mobile station by transmission on a radio channel and to relay to the switching unit an encoded uplink speech signal received from the mobile station by transmission on the transmission link; and means for marking a monitoring interval if a predetermined number of one of downlink and uplink blocks is conveyed erroneously over said transmission link during said monitoring interval and for reporting said transmission link as having poor quality if a predetermined number of monitoring intervals are marked within a predetermined time period.
Claim 3
Dependent Claim
18 words
The system of claim 1, wherein said means for marking and determining is disposed in said switching unit.
Claim 4
Dependent Claim
25 words
The system of claim 1, wherein said means for marking and determining evaluates said transmission link based on blocks which are received on said downlink.
Claim 5
Dependent Claim
25 words
The system of claim 1, wherein said means for marking and determining evaluates said transmission link based on blocks which are received on said uplink.
Claim 6
Dependent Claim
13 words
The system of claim 1, wherein said transmission link is a PCM link.
Claim 7
Dependent Claim
126 words
The system of claim 1, further comprising: in the switching unit, link transmission means including: means for generating an error detection code from the encoded downlink speech signal; and formatting means, coupled to the generating means, for producing a formatted downlink block to be transmitted on the transmission link, the formatted downlink block having a header, the encoded downlink speech signal, and the error detection code; and in the base station, link error detecting means for signalling existence of an error in a received downlink block in response to the received downlink block containing an error to said means for marking and determining, wherein said means for marking and determining includes a counter for counting a number of blocks having errors in each said monitoring interval.
Claim 8
Dependent Claim
16 words
The system of claim 6, wherein the error detection code is a cyclic redundancy check code.
Claim 9
Dependent Claim
126 words
The system of claim 1, further comprising: in the base station, link transmission means including: means for generating an error detection code from the encoded uplink speech signal; and formatting means, coupled to the generating means, for producing a formatted uplink block to be transmitted on the transmission link, the formatted uplink block having a header, the encoded uplink speech signal, and the error detection code; and in the switching unit, link error detecting means for signalling existence of an error in a received uplink block in response to the received uplink block containing an error to said means for marking and determining, wherein said means for marking and determining includes a counter for counting a number of blocks having errors in each said monitoring interval.
Claim 10
Dependent Claim
16 words
The system of claim 8, wherein the error detection code is a cyclic redundancy check code.
Claim 11
Dependent Claim
34 words
The system of claim 1, wherein said predetermined number of blocks is two, said monitoring interval is one second, said predetermined number of monitoring intervals is two, and said time period is five seconds.
Claim 12
Dependent Claim
103 words
The system of claim 1, further comprising: in the switching unit, an apparatus comprising: input means for receiving a signal indicative of existence of an error in a received uplink block; and uplink error handling means, coupled to the input means, for discarding a received uplink block in response to the signal indicating existence of an error therein, and for substituting therefor a substitute block including encoded speech data stored from a previously received uplink block, wherein said means for marking and determining includes a counter for counting a number of said signals received by said input means in each said monitoring interval.
Claim 13
Dependent Claim
202 words
A digital cellular communications system comprising: a bidirectional transmission link for conveying encoded speech and control data in a block format; a switching unit coupled to a first end of the transmission link, the switching unit including: a speech encoder for encoding speech signals; means for generating an error detection code from the encoded speech signal; and formatting means, coupled to the generating means, for producing a formatted downlink block to be transmitted on the transmission link, the formatted downlink block having a header, the encoded speech data, and the error detection code; a base station coupled to a second end of the transmission link, the base station including link error detecting means for signalling existence of an error in a received downlink block in response to the received downlink block containing an error; first means for receiving said signalled error existence from said base station and generating an error signal if a first rate of erroneously received downlink blocks exceeds a first threshold; and second means for filtering an output of said first means by comparing a second rate at which said error signals are generated to a second threshold to distinguish between faulty and normal behavior of said transmission link.
Claim 14
Dependent Claim
202 words
A digital cellular communications system comprising: a bidirectional transmission link for conveying encoded speech and control data in a block format; a switching unit coupled to a first end of the transmission link, the switching unit including: a speech encoder for encoding speech signals; means for generating an error detection code from the encoded speech signal; and formatting means, coupled to the generating means, for producing a formatted downlink block to be transmitted on the transmission link, the formatted downlink block having a header, the encoded speech data, and the error detection code; a base station coupled to a second end of the transmission link, the base station including link error detecting means for signalling existence of an error in a received downlink block in response to the received downlink block containing an error; first means for receiving said signalled error existence from said base station and generating an error signal if a first rate of erroneously received downlink blocks exceeds a first threshold; and second means for filtering an output of said first means by comparing a second rate at which said error signals are generated to a second threshold to distinguish between faulty and normal behavior of said transmission link.
Claim 15
Dependent Claim
16 words
The system of claim 12, wherein the error detection code is a cyclic redundancy check code.
Claim 16
Dependent Claim
13 words
The system of claim 12, wherein the transmission link is a PCM link.
Claim 17
Dependent Claim
14 words
The system of claim 12, wherein said first threshold is two blocks per second.
Claim 18
Dependent Claim
18 words
The system of claim 12, wherein said second threshold is two out of five most recent time intervals.
Claim 19
Dependent Claim
118 words
The system of claim 12, wherein the base station further comprises: means for generating an error detection code from an encoded speech signal received from a mobile station; and formatting means, coupled to the generating means, for producing a formatted uplink block to be transmitted on the transmission link, the formatted uplink block having a header, the encoded speech signal, and the error detection code, and wherein the switching unit further comprises: said first means monitoring a number of erroneously received uplink blocks over a predetermined time interval; and link error detecting means for signalling, to said first means, existence of an error in a received uplink block in response to the received uplink block containing an error.
Claim 20
Dependent Claim
25 words
The system of claim 17, wherein said first means generates said error signal if a rate of erroneously received uplink blocks exceeds said first threshold.
Claim 21
Dependent Claim
76 words
The system of claim 17, further comprising: in the switching unit, an apparatus comprising: input means for receiving a signal indicative of existence of an error in a received uplink block; and uplink error handling means, coupled to the input means, for discarding a received uplink block in response to the signal indicating existence of an error therein, and for substituting therefor a substitute block including encoded speech data stored from a previously received uplink block.
Claim 22
Dependent Claim
17 words
The system of claim 12, wherein said first and second means are disposed in said switching unit.
Claim 23
Independent Claim
106 words
A method for supervising a data transmission link comprising the steps of: counting a number of erroneously received blocks of data which have been transmitted through said data transmission link over a predetermined period of time; determining if said number exceeds a first threshold; selectively categorizing said period of time as a bad time period based upon said determination; storing said categorization of said period of time; evaluating a plurality of recent categorizations to determine if a number of bad time periods exceeds a second threshold; and selectively reporting that said data transmission link has insufficient quality based upon a result of said step of evaluating.
Claim 24
Independent Claim
106 words
A method for supervising a data transmission link comprising the steps of: counting a number of erroneously received blocks of data which have been transmitted through said data transmission link over a predetermined period of time; determining if said number exceeds a first threshold; selectively categorizing said period of time as a bad time period based upon said determination; storing said categorization of said period of time; evaluating a plurality of recent categorizations to determine if a number of bad time periods exceeds a second threshold; and selectively reporting that said data transmission link has insufficient quality based upon a result of said step of evaluating.
Claim 25
Dependent Claim
14 words
The method of claim 21, wherein said data transmission link is a PCM link.
Claim 26
Dependent Claim
12 words
The method of claim 21, wherein said first threshold is two blocks.
Claim 27
Dependent Claim
20 words
The method of claim 21, wherein said second threshold is two bad time periods within a last five time periods.
Claim 28
Dependent Claim
17 words
The method of claim 21, further comprising the step of: correcting said erroneously received blocks of data.
Claim 29
Independent Claim
129 words
A method for handling a connection between a switching unit and a base station using one of a plurality of transmission links comprising the steps of: monitoring, for each of said plurality of transmission links, a number of erroneously received blocks over a predetermined time interval; selectively marking time intervals based upon a result of said monitoring step; distinguishing between faulty and normal behavior of each of said plurality of transmission links based upon a time distribution of said marked time intervals; selecting as said one of said plurality of data transmission links, a transmission link which has not been identified as faulty for handling said connection; and setting up said connection between said switching unit and said base station using said selected one of said data transmission links.
Claim 30
Independent Claim
129 words
A method for handling a connection between a switching unit and a base station using one of a plurality of transmission links comprising the steps of: monitoring, for each of said plurality of transmission links, a number of erroneously received blocks over a predetermined time interval; selectively marking time intervals based upon a result of said monitoring step; distinguishing between faulty and normal behavior of each of said plurality of transmission links based upon a time distribution of said marked time intervals; selecting as said one of said plurality of data transmission links, a transmission link which has not been identified as faulty for handling said connection; and setting up said connection between said switching unit and said base station using said selected one of said data transmission links.
Claim 31
Dependent Claim
13 words
The method of claim 26, wherein said data transmission links are PCM links.
Claim 32
Dependent Claim
51 words
The method of claim 26, further comprising the steps of: continuing, after said step of setting up said connection, to monitor said number of erroneously received blocks of said selected one of said data transmission links; and if said selected one of said data transmission links becomes faulty, taking remedial action.
Claim 33
Dependent Claim
20 words
The method of claim 28, wherein said step of taking remedial action further comprises the step of: disconnecting the connection.
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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) | 2001-05-25 | 2001-11-24 | 2002-05-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-05-25 | 2005-11-24 | 2006-05-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-05-25 | 2009-11-24 | 2010-05-26 | $7700.00 | Window Closed / Lapsed |