JPH09121206A - Bit error rate measuring method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify the constitution of a base station to reduce operator's burden. SOLUTION: An unique word (UW) in a reception signal is detected by an UW detection circuit 14, and its bit error is detected by a bit error detection circuit 16, and the detected bit error is totalized by a CPU 18 to obtain the bit error rate in the reception signal. The obtained bit error rate is made correspond to position information by a personal computer to obtain the bit error rate distribution, thus specifying the service area of the base station.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bit error rate measuring method executed to evaluate the quality of serial data transmission.

[0002]

2. Description of the Related Art A mobile radio for performing radio communication between a base station fixedly arranged and a mobile station mounted on a vehicle or other mobile body or carried by a human. When operating the system, the operator grasps the service area of the base station (range in which normal wireless communication with the mobile station is possible) so that the base station and the mobile station can communicate normally and with high quality signals. There is a need. One way to know whether or not a certain point belongs to the service area of the base station is that the occurrence rate of bit error (bit error) in the serial data signal wirelessly received from the base station at that point (bit error). The error rate) is measured. In the conventional method, a PN (pseudo noise) code that is not used for normal communication is first transmitted to the base station 100 shown in FIG.
Wirelessly transmitted from the mobile station 200, the measuring device 300 having a movable structure similar to the mobile station 200 receives the PN code, and the bit error rate of the received PN code is evaluated. The typical drawback of this method is that PN
That is, the PN generator 100A for generating the code must be provided in the base station 100. This leads to a complicated configuration of the base station 100. Furthermore, when the measurement device 300 measures and evaluates the bit error rate, the PN generator 100A, which is not used for normal communication, must be operated. This was a burden on the operator.

A first object of the present invention is to use a part of a serial data signal in normal communication for measuring a bit error rate, so that it is necessary to measure the bit error rate as in a service area check. To provide a bit error rate measuring method that does not require a special device (PN generator 100A in the above example) to operate at the transmission source of the serial data signal (base station 100 in the above example) at some time. is there. A second object of the present invention is to achieve the first object by simplifying the device configuration of the transmission source of the serial data signal, enabling the system to be implemented at low cost, and reducing the burden on the operator of the system. To reduce operating costs.

[0004]

In order to achieve such an object, the bit error rate measuring method according to the first configuration of the present invention provides a known pattern from a received serial data signal. A first step of detecting a unique word (UW) and a second step of detecting a bit error in the detected UW by collating with a standard relating to the UW.
And a third step of estimating a bit error rate in the serial data signal based on the occurrence frequency of bit errors that are sequentially detected. According to this configuration, since the bit error is detected from the UW used for signal timing acquisition during normal communication and the bit error rate in the serial data signal is estimated based on this, the serial error is measured when the bit error rate is measured. There is no need to operate a special device at the source of the data signal. As a result, the device configuration of the transmission source of the serial data signal can be simplified, the system can be implemented at low cost, and the burden on the operator of the system can be reduced and the operating cost can be reduced.

In the bit error rate measuring method according to the second configuration of the present invention, in the first configuration, the first and second steps are executed for a plurality of serial data signals received at a single measurement position. The bit error rate at the measurement position is estimated by performing the third step above. According to this configuration, the UW bit error is detected for a plurality of serial data signals and the bit error rate is obtained based on the result. Therefore, the UW which is only a part of the serial data signal is used. Regardless, the bit error rate can be measured with high accuracy.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. The same components as those of the conventional technique shown in FIG. 4 are designated by the same reference numerals and the description thereof will be omitted.

FIG. 1 shows the configuration of a mobile radio system according to an embodiment of the present invention. In this embodiment, the base station 100 is not provided with the PN signal generator 100A. That is, the measuring device 3 does not wirelessly transmit the PN code not used for normal communication from the base station 100.
This embodiment is characterized in that the bit error rate measurement using 00A (for example, a specific service in a service area) can be executed. Therefore, in the present embodiment, the configuration of the base station 100 is simplified, and conventionally, the PN generator 1 is used at the time of measurement.
The burden on the system operator who had to operate 00A is reduced.

FIG. 2 shows a measuring device 30 according to this embodiment.
An example configuration of 0A is shown. The measuring device 300A shown in this figure is a downlink signal transmitted from the base station 100 to the mobile station 200 and / or the mobile station 200 to the base station 100.
It is provided with an antenna 10 and a receiving circuit 12 for intercepting an upstream signal transmitted to. The reception circuit 12 demodulates the signal received by the antenna 10, and the UW detection circuit 14 at the subsequent stage demodulates the UW of an arbitrary slot in the demodulated signal.
(See FIG. 3). Further, the bit error detection circuit 16 in the subsequent stage compares the bit error occurring in the detected UW with the UW information defined in STD-28 or the like, that is, a code sequence predetermined as UW. To detect. The CPU 18 repeatedly executes these UW detection and bit error detection operations over a predetermined number of slots, and estimates the bit error rate in the received signal based on the result. The personal computer 20 compares the estimated bit error rate with a predetermined criterion. As a result, when it is determined that the bit error rate is better than the determination criterion, the personal computer 20 considers that the position where the measuring instrument 300A is currently located is within the service area of the base station 100. On the contrary, when it is determined that the bit error rate is worse than the determination standard, the personal computer 20 is currently using the measuring device 3
The position where 00A exists is considered to be outside the service area of the base station 100. The personal computer 20 associates this determination result with the separately generated position information,
The distribution of bit error rates is obtained and the service area of the base station 100 is specified (area mapping).

Incidentally, FIG. 3 shows a general structure of one slot of a serial data signal. In the figure,
"Bit synchronization" is a clock for synchronizing operations between transmission and reception, "keyword" corresponds to a command to the receiving side, and "error detection" is a code for detecting an error occurrence in the slot. Further, the UW is usually used by the mobile station 200 to capture a slot. Therefore, the mobile station 200 also normally uses the UW detection circuit. When realizing the measuring instrument 300A according to this embodiment, the UW detection circuit used in the mobile station 200 can be diverted.

[0010]

[Addendum] The above description has been made on the assumption of a mobile wireless system such as a PHS (Personal Handyphone System), but the present invention can be applied to any system that transmits and receives serial data signals without distinction between wireless and wired systems. .

[Brief description of the drawings]

FIG. 1 is a layout diagram showing a configuration of a mobile radio system according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of a measuring instrument.

FIG. 3 is a conceptual diagram showing a configuration of a serial data signal wirelessly transmitted between base station mobile stations.

FIG. 4 is a layout diagram showing a configuration of a mobile radio system according to a conventional technique.

[Explanation of symbols]

10 antennas, 12 reception circuits, 14 UW detection circuits, 16-bit error detection circuits, 18 CPU, 20
Personal computer, 100 base station, 200 mobile station, 300A measuring instrument.

Claims (2)

[Claims] 1. A first step of detecting a unique word as a known pattern from a received serial data signal, and a second step of detecting a bit error in the detected unique word by collating with a standard relating to the unique word.
A bit error rate measuring method comprising: a step; and a third step of estimating a bit error rate in the serial data signal based on a bit error occurrence frequency that is sequentially detected. 2. The bit error rate measuring method according to claim 1, wherein the first and second steps are executed for a plurality of serial data signals received at a single measurement position, and then the third step is executed. The bit error rate measuring method is characterized by estimating the above-mentioned bit error rate at the measurement position.