METHOD FOR MEASURING COVERAGE IN MOBILE TELEPHONE NETWORKS

Abstract: The invention relates to a method for measuring coverage in mobile telephone networks. Fixed measuring stations measure signal strength and signal identity from a mobile transmitter station. The transmitter station utilises a single frequency and moves over the area in question. The transmitter station registers its position and the measuring stations obtain a reference between measurement result and position. By carrying out the coverage measurement in the uplink, that is to say from mobile station to fixed measuring station, a method which is more economical with frequencies can be utilised.

Description: TITLE OF THE INVENTION : METHODFORMEASURINGCOVERAGE IN MOBILE TELEPHONE NETWORKS FIELD OF THE INVENTION The present invention relates to a method for measuring coverage in mobile telephone networks. Coverage measurements of base stations in a mobile telephone network are carried out in such a manner that the operator of the network obtains knowledge about the range of radio coverage of the base stations. In the invention, synchronized signal strength measurements in the uplink are utilised for minimising capacity losses and loss of income in the network due to the fact that only one frequency needs to be utilised for the measurement. PRIOR ART Measuring the range of coverage of base stations is nowadays carried out by a mobile measuring station measuring the signal strength in one channel per base station in the downlink (base station to mobile station), see Figure 1. The measuring station registers signal strength, signal identity and current position. These data are used as the basis for the coverage diagrams for the respective base stations. To be able to measure the signal strength from a base station down to noise level, all channel units in the same channel and all channel units in adjacent channels must be shut down within a large geographic area in order to reduce potential interference during the measurements. If several base stations are measured at the same time a not inconsider- able number of channel units must be shut down. A problem is that capacity is lost in the network and, with that, the incomes from calls are also reduced. These measure¬ ments are therefore normally carried out during the night, when the traffic load is low and is carried by a limited number of base stations. SUMMARY OF THE INVENTION The present invention provides a method for measuring coverage in mobile telephone networks, which solves the above-mentioned problems. According to the invention, fixed measuring stations measure signal strength and signal identity from a mobile transmitter station. The transmitter station sends on a single frequency and moves over the area in question. The trans¬ mitter station regularly registers the position. The measuring stations obtain a reference between measurement result and position. BRIEF DESCRIPTION OF THE DRAWINGS The invention is described in detail below with reference to the attached drawing, wherein Figure 1 shows a coverage measurement in the downlink according to the prior art, and Figure 2 shows a coverage measurement in the uplink according to the present invention. DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS Figure 1 shows how a coverage measurement is carried out today. As mentioned above, the measurement is carried out in the downlink, that is to say from the base station to the mobile, whereby separate frequencies fl, f2, f3, f4 and so forth are occupied for each base station so that the mobile station will be able to carry out the measurement without interference and with know¬ ledge of the identities of the base stations. According to the present invention, the coverage measurement is carried out on the uplink, that is to say mobile station to base. The measuring stations are in this case located in the base stations. The measuring stations measure the signal strength and signal identity from a mobile transmitter station, which transmits on a single frequency fl, that is to say only one channel is utilised. The total capacity loss is limited to one to three channels - the channel on which the measurement is carried out and possibly one to two adjacent channels. The channels in question can be selected freely and preferably in such a manner that channels which are poorly utilised in the network are used. If the measurement can be located outside the frequency band used by the radio network, the capacity loss is avoided. The mobile station regularly registers its position. The measuring stations obtain a reference between the measurement result and the current position. The mobile station moves over the current area until the surface coverage is considered to be adequate. The advantage with the method according to the invention is thus a diminished loss of capacity in the network during the measurement, which provides a lower loss of income from calls. This is economically advan¬ tageous. The limited capacity loss also means that these measurements can be carried at other times than during the night and over several base stations for each measur¬ ing cycle. The invention is only limited by the patent claims below.

Claims: PATENT CLAIMS 1. Method for measuring coverage in mobile telephone networks, characterised in that fixed measuring stations measure signal strength and signal identity from a mobile transmitter station, which transmitter station transmits at a single frequency and moves over the area in question. 2. Method according to Claim 1, characterised in that the transmitter station registers its position during its movement through the area and in that the measuring stations obtain a reference between measurement result and position.

Inventors: STJERNHOLM PAUL, STJERNHOLM, PAUL
Applicants: STJERNHOLM PAUL, TELEVERKET
Application year: 1993
Main classification: H04B7
IPC codes: H04W16