Multiplex communications – Diagnostic testing – Determination of communication parameters
Patent
1996-09-20
1998-11-03
Olms, Douglas W.
Multiplex communications
Diagnostic testing
Determination of communication parameters
370337, 370347, 370350, 455 674, H04Q 734, H04B 1700
Patent
active
058319743
DESCRIPTION:
BRIEF SUMMARY
This application claim benefit of international application PCT F195/00639, filed Nov. 20, 1995
FILED OF THE INVENTION
The present invention relates to a testing equipment for a base station network in a time division multiple access (TDMA) radio system employing timing advance control, in which a maximum value defined for a timing advance determines a maximum distance between a base station and a mobile station, this testing equipment being located at one base station site under control of the respective base station to perform test procedures on base stations, the testing equipment simulating the operation of a normal mobile station on the radio path during the test procedures.
BACKGROUND OF INVENTION
In radio systems, for instance in cellular systems, one of the most crucial factors is the quality of the radio connection between a base station and a mobile radio station. The quality of this radio connection is essentially affected by the condition of the radio sections, i.e. the antennas and transceivers, of the base station. Therefore, it is important that the condition of a base station can be monitored by means of different measurements and tests.
In a known solution, a base station is provided with a testing equipment with a dedicated antenna and a transceiver so that it is capable of establishing a connection with the base station over the radio path, like a normal subscriber station. In addition, the testing equipment is provided with necessary measuring equipment for performing desired test measurements and test calls on the base station. A testing equipment located at one base station site can also be used for measuring neighboring base stations, whereby a dedicated testing equipment for each base station is avoided.
In digital time division multiple access (TDMA) radio systems, a number of mobile radio stations can use the same carrier wave (radio channel) on the time division principle for communicating with a base station. The carrier wave is divided into successively recurring frames, which are divided further into time slots, for instance into eight time slots, which are allocated to users as the need arises. Short data bursts are transmitted in the time slots. A mobile radio station synchronizes with a signal arriving from the base station and transmits a burst in accordance with this synchronization signal (or "sync") in such a manner that the burst of the mobile station is received at the base station in a time slot allocated to this specific mobile station. However, mobile stations may be located at different distances from the base station, it being thus necessary to synchronize the transmission moment of each mobile station with the base station, taking into account the propagation delay due to this distance in such a manner that the signal from each mobile station, regardless of its distance from the base station, is received in the correct time slot at the base station. In order to do this, the base station measures the time difference between its own transmission and the transmission received from a mobile station and determines a suitable timing advance for the mobile station on this basis. By means of this timing advance, the mobile station advances the transmission moment in relation to the basic moment provided by the sync obtained from the base station. Different factors internal to the system restrict the highest possible timing advance to a certain maximum value. This maximum value of timing advance then determines the largest cell size that a base station of the system is able to serve. For instance in the pan-European mobile communication system GSM (Global System for Mobile Communication), timing advance may be given values within a range of 0-233 .mu.s, which is equivalent to the size of a cell with a radius of 35 km at the most.
This restriction due to timing advance also leads to the fact that a testing equipment located at one base station site cannot be used for testing neighboring base stations which are located at an excessive distance from the testing equipm
REFERENCES:
patent: 3350644 (1967-10-01), McNair
patent: 5278832 (1994-01-01), Binzel et al.
patent: 5363375 (1994-11-01), Chuang et al.
patent: 5471649 (1995-11-01), Rees et al.
patent: 5483537 (1996-01-01), Dupuy
patent: 5544171 (1996-08-01), Godecker
patent: 5654960 (1997-08-01), Kohlschmidt
Nokia Telecommunications Oy
Olms Douglas W.
Rao Seema S.
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