Abstract: The present invention relates to the operation and maintenance of radio base stations in mobile communication systems. An inventive radio base station, which can be upgraded remotely in a safe way. In one embodiment of the invention, the radio base station comprises a file system comprising different versions of files, so that an old version of a file can be reverted to should problems in the operation of the radio base station occur. In another embodiment of the invention, the radio base station comprises a back-up area in which a copy of the files of the file system are stored. The back-up area is independent of the file system, so that if problems with the files in the file system are detected, the contents of the back-up area can be stored in the file system.

Abstract: A hierarchical fault handling system and method based on filtering data regarding entities in the system and coordinating said filtered data in order to determined if an entity is considered faulty or not. The result for all entities is coordinated in a system fault coordinating means (17) which makes the overall decision if the system considered to be faulty or not.

Abstract: The present invention relates to the operation and maintenance of radio base stations in mobile communication systems. An inventive radio base station, which can be upgraded remotely in a safe way. In one embodiment of the invention, the radio base station comprises a file system comprising different versions of files, so that an old version of a file can be reverted to should problems in the operation of the radio base station occur In another embodiment of the invention, the radio base station comprises a back-up area in which a copy of the files of the file system are stored. The back-up area is independent of the file system, so that if problems with the files in the file system are detected, the contents of the back-up area can be stored in the file system.

Abstract: A hierarchical fault handling system and method based on filtering data regarding entities in the system and coordinating said filtered data in order to determine if an entity is considered faulty or not. The result for all entities is co-ordinated in a sys-tem fault co-ordinating means (17) which makes the overall decision if the system considered to be faulty or not.

Abstract: A method and apparatus for evaluating interference within a timeslot of a received TDMA signal is described. An average received signal strength is calculated for a plurality of repeating segments within a TDMA timeslot. The segment sizes are dependent upon the efficiency of the error correction coding scheme utilized by a selected channel type. The calculated received signal strengths for the plurality of the segments are applied to a lowpass filter. The output of the lowpass filter is processed to determine the level of interference within the timeslot.

Abstract: A method and apparatus for evaluating interference within a timeslot of a received TDMA signal is described. An average received signal strength is calculated for a plurality of repeating segments within a TDMA timeslot. The segment sizes are dependent upon the efficiency of the error correction coding scheme utilized by a selected channel type. The calculated received signal strengths for the plurality of the segments are applied to a lowpass filter. The output of the lowpass filter is processed to determine the level of interference within the timeslot.

Abstract: A method and apparatus for evaluating interference within a timeslot of a received TDMA signal is described. An average received signal strength is calculated for a plurality of repeating segments within a TDMA timeslot. The segment sizes are dependent upon the efficiency of the error correction coding scheme utilized by a selected channel type. The calculated received signal strengths for the plurality of the segments are applied to a lowpass filter. The output of the lowpass filter is processed to determine the level of interference within the timeslot.

Abstract: A cellular network is controlled such that time slots of transmissions from base stations with the same operating frequency are synchronized. Moreover, adjacent base stations using the same frequency are controlled such that, at any given time, they are transmitting different sync words.

Abstract: A method is described of measuring the burst quality of a received signal. Specifically, the impairment correlation matrix, used to provide an estimate of impairment correlation properties for use in demodulating radio signals received by a plurality of antennas, is used to obtain the parameters necessary to obtain measurements of the burst quality, with respect to the signal to noise ratio and the signal to interferer ratio respectively. Specific algorithms for calculating the burst quality are also disclosed.

Abstract: A base station monitors signals received from cochannel interferers, and detects the air frame positions of the interfering transmissions. The base station then adjusts the air frame position of its own transmissions such that it minimizes the possibility of interference with the cochannel interferers.

Abstract: Methods and systems for measuring signal noise of supervisory audio tones (SATs) in radiocommunication systems are disclosed. Exemplary embodiments involve extracting a real component from a received SAT signal, removing the SAT signal portion and examining the remainder to determine a noise component present in the SAT. The noise component can be compared with a signal strength measurement to obtain a signal-to-noise ratio.

Abstract: Methods and systems for estimating Supervisory Audio Tone (SAT) strength during data transfer and for a short time period thereafter. The SAT during this period is regarded as being identical to the strength measured just before the data transfer was started. In an alternative embodiment, a probabilistic algorithm can be used wherein previous measurements are used to predict the SAT strength during and for a period after data transfer. Where the present invention is used in a mobile radio telecommunications system of the type in which analog information is transmitted between at least one base station and a number of mobile stations, a method for supervising the quality of a connection between the base station and a mobile station includes transmitting data between the base station and the mobile station during which a SAT is not transmitted and using pre-data transfer SAT measurement for radio transmission quality supervision during at least a time period of said data transmitting step.

Abstract: A method and apparatus for controlling the use of discontinuous transmission in a cellular telephone. The preferred embodiment of the present invention includes a voice activity detector for detecting the presence or absence of speech and an energy detector for measuring the energy level of sound input to a microphone of a cellular telephone during the absence of speech. The present invention also includes a comparator for comparing the measured noise energy level against a threshold value. The determination as to the presence or absence of speech and the output of the comparator are provided to a controller. The controller enables discontinuous transmission when the energy level detected during the absence of speech is less than or equal to the threshold value and disables discontinuous transmission when the measured energy level exceeds the threshold value.

Abstract: Synchronization is maintained between a regional radio transmitter/receiver and a remote transmitter/receiver communicating across a TDMA channel by detecting time misalignment of communications from the remote transmitter/receiver to the regional transmitter/receiver, commanding the remote transmitter/receiver to adjust its transmission timing, and, until the remote transmitter/receiver has adjusted its transmission timing, looking for a synchronization pattern accompanying transmissions by the remoter transmitter/receiver during two discontinuous time intervals, one centered about a time of occurrence of the synchronization pattern before the command and another centered about an expected time of occurrence of the synchronization pattern in response to the command. Effectively, what would otherwise be a disadvantageously wide time window is split into two advantageously narrow time windows to avoid detection of false syncs. Fewer false syncs are detected, and speech quality is increased.