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: 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.