JPS5944134A - Method for encoding identification code of radio communication system - Google Patents

Abstract

PURPOSE:To prevent an identification code read-only memory from troubles due to intentional or interesting operations by adding a check bit to the identification code read-only memory in accordance with the same code rule as an error correcting method to record an identification code of each moving subscriber. CONSTITUTION:To the identification code recorded in the identification code read-only memory (IDROM) 6 of a moving station 8, a check bit having the same code rule as the code communication method is added. A control signal received from a base station and demodulated is composed and then stored in a register of an operation processing part 5. The information in the IDROM 6 is also stored in the register of the operation processing part 5. When moving station number designating signals coincide with each other, the operation processing part 5 generates a calling response signal by the two signals stored in the register. In this case, Hargelbarger code is used as the code.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field to which the Invention Pertains] The present invention relates to a wireless communication system related to an automobile subscriber telephone system. In particular, in wireless communication systems that include a small number of base stations and a large number of mobile subscribers, each subscriber is uniquely assigned in order to specify the subscriber's mobile device number, service area, and optional functions. The present invention also relates to an encoding system for identification fishing numbers.

[Description of prior art]

In the above-mentioned wireless communication system, each mobile subscriber's device is assigned a unique identification code in order to identify the subscriber's mobile device number, service area, various optional functions, etc. The identification code of each mobile subscriber is stored in a read-only memory (hereinafter abbreviated as 'IDROM').
is configured to record. Since the subscriber mobile device is managed by each subscriber who is a customer, it is possible for the subscriber to tamper with this IDROM either maliciously or out of f1J taste. Such manipulations can be used to receive or intercept calls made to other subscribers, to shift charges to other subscribers, or to provide free optional features for which the subscriber has not subscribed. It becomes possible to use it.

In order to prevent this, a method has been considered in which the records of the IDROM are encrypted and a decoding circuit is provided inside the mobile device to decode and utilize the output code of the IDROM. However, this method requires that each mobile device be equipped with a crude I and L decoding circuit, which has the disadvantage that the device 6 becomes expensive.

On the other hand, in recent thermal storage communication systems, communication is performed using an error correction system in order to transmit various numbers, and each mobile device is equipped with a processing circuit for this purpose.

The present invention focuses on the use of this processing circuit also for decoding the above-mentioned code.

[Purpose of the invention]

An object of the present invention is to provide a method that can encrypt IDROM records without providing a special encryption/decryption circuit in each subscriber's mobile device, thereby eliminating inconveniences caused by malicious or curious manipulation of the IDROM. purpose.

[Key points of the invention]

In the present invention, check pits are added to the IDROM according to the same code rule as the error correction method used in the system, and the digit code of each mobile subscriber is recorded, and the code read from this IDROM has the above-mentioned error. It is characterized in that it is configured to be used via a correction type decoding processing circuit.

[Implementation, explanation of examples]

FIG. 1 is a block diagram of an individual packaging Vj according to the present invention. A transmitting/receiving section 2 for transmitting and receiving data is connected to the transmitting/receiving antenna common section 1, and this transmitting/receiving section 2 is connected to an arithmetic processing section 3 coupled to a signal processing section 4 to form a mobile phone base station 7. be done.

Further, a transmitting/receiving section 2 for transmitting and receiving data is connected to the transmitting/receiving antenna common section 1.This transmitting/receiving section 2 is connected to an arithmetic processing section 5 coupled to a signal processing section 4, and further connected to this arithmetic processing section 5. A mobile device 8 is configured by connecting the IDROMs 6 of a large number of subscriber mobile devices. Above base station 7&J1
Since a multi-channel access method is used with the mobile station 8, the mobile unit number designation signal, service area designation signal, etc. 99 through the transmitter/receiver section 2 and the antenna common section 1, and sends it as a control signal to the mobile unit 112:.

On the other hand, the mobile (I) is 1, and the control signal (M) sent from the base station is demodulated by the transmitting/receiving unit 2 through the antenna common unit 1. The signal processing unit 4 decodes the signal under the control of the signal processing unit 4 and stores it in a register in the arithmetic processing unit 5.

The IDROM 6 stores information such as the designation of the mobile device number, the service area, and the optional function, which are coded using the same coding method as that used in the signal processing unit 4. ing.

Under the control of the arithmetic processing unit 5, this 1. The information is decoded by the signal processing section 4 and stored in the register of the arithmetic processing section 5.

The arithmetic processing unit 5 generates an incoming call response signal when the two signals stored in the register match the mobile device number designation signal, etc., and controls the signal processing unit 4 to encode the signal. The initialized signal is sent to the base station 7 as an incoming call response signal through the transmitting/receiving section 2 and the antenna common section 1. Next, the call channel designation is sent from the base station to the mobile device (E-), 1
1, which is also encoded and decoded in the same way.

Optional function designation information is also recorded in the IDROM 6 in the form of a shrine symbol. Therefore, each time the specified information is refreshed under the control of the arithmetic processing unit 5, the specified information is
The data from the DROM 6 is also transmitted to the signal processing unit 4, decoded, and stored in a register of the arithmetic processing unit 5. Based on this stored information, the arithmetic processing unit 5 determines the presence or absence of an optional function and sends it to an optional terminal, etc. (V
control the number.

This more f? When using the J encoding method, if the internal information of the IDROM is manipulated, it will be detected as an error when it is decoded by the processor 4 of FIG.
The operation of the moving 8 iso stops due to an OM error. Therefore, it will not take many months due to IDROM manipulation (,
You will also be less likely to cause trouble to other people.

Moreover, is it used in this kind of method? (The original purpose of r+ 4M conversion, that is, the error correction function, is that even if the arithmetic processing unit 5 in FIG. 1 detects one error from the transmitting/receiving unit 2, It has a J stop function and is controlled by '5, which can prevent IDROM from being misused without losing the original meaning of encoding.In addition, for this purpose, a special decoding kit for IDROM is included. There is no need to create a new signal processing section.

Next, a specific example of the encoding circuit and decoding circuit of the signal processing section of the present invention will be shown.

Figure 2 shows Hagelbarger/6-gar.
) An example of an I0 encoding circuit using the encoding method is shown. That is, the first and fourth stages of the shift register 9 are input to the selective register 16, and its output check bit 17 and shift register output DATA 18 are connected to the switching unit 10. in is an information source to be encoded, and is sent from the arithmetic processing unit 5 of the 11th FI. Shift register 9 of the second
The signal sent serially is left in line with the synchronization signal (CHECKBIT).
17 is the exclusive OR of the states of the first and fourth stages of the shift register 9. 11'+external output δ is the output data 18 of the final stage of the shift register 9 and this check bit 1.
7 and 7 are alternately switched and transmitted by the switching unit 10. Therefore, this W''+I;11 output 6 is such that the bits of the upper jfL''1 data 18 and the check bit 17 are sent out alternately. This number 1 is sent to the performance processing unit 5 in FIG. 1, and then sent to the base station 7 via a wireless line.

FIG. 3 is an example of a decoding circuit using the No-Kellberger code shown in FIG. 2.
The first and fourth stages of the shift register 12 on the side are input to the exclusive OR circuit 19, and one goonic bit 1
7' is input to the shift register 13, and its seventh (final) stage and the output of the exclusive OR circuit 19 are input to the exclusive OR circuit 20. Its output or syndrome (S
This syndrome 21 is input to one terminal of the exclusive OR circuit 23 and the AND circuit 22, and the output of the AND circuit is input to the other input of the exclusive OR circuit 23. Connected. The third stage of the shift register 14 connected to the output of this exclusive OR circuit 23 is connected to the other input terminal of the AND circuit 22, and further, the output of this AND circuit 22 and the shift register 120 The output of the second stage is connected to the input of the altruistic OR circuit 240. The sent signal is separated into data and check bits by the switching section 11, and then sent to and pulled from other shift registers 12 and 13. The exclusive OR of the states of the first and fourth stages of the shift register 12 has no error when compared with the value of the final stage of the shift register 13, and Jl becomes equal, so the syndrome is I'O
It becomes J. If there is a mistake, the syndrome is rl
, and when decoding IDROM, Ct
, calculations j (the manufacturing unit 5 calculates the IDR from this syndrome signal)
It is treated as an OM error and the operation of the mobile device 8 is stopped. In the case of the control signal sent from the Mabu base station 7, +J This syndrome signal is sent to X: to perform error prevention by IL as follows.

The final stage σ) bit of the shift register 12 of data 18' in the figure uses the check bit 17' of the syntrail bit.
This is included in the last stage bit of cluster 13, and the check hits of four MOs are also included.Therefore, both the current syndrome and the previous syndrome are 0''1. St) λt is the final stage σ) bit of the shift register 12 (↓ It can be determined that there is an error. Shift register 14G ↓ This is a buffer that stores the information of the syndrome four times before this. Shift If it is determined that there is an error in the bits of the register 12 and ↓<>, it can be determined that there is no error in the first stage bit of the shift register.

Therefore, if this first stage bit is the final stage trap, and it comes to 17, even though the first stage hit at this point is b'RC4, both the syndrome at this point and the 4th previous Jintrom are rl. , and a non-error bit may be determined to be an error. The 191-alternative OR circuit 20 inserted between the shift registers 13 and 14 is used to return the error-corrected syndrome to 1''OJ so that the above-mentioned malfunction does not occur.

If the check bit is erroneous, if 16 healthy bits encoded in one line follow, there is only one syndrome '1J, so no error correction is performed.

The bit determined to be erroneous in this manner is inverted by exclusive OR to 61J-, which is sent as data and sent to IPI, and sent to the U9 processing unit. The encoded signal contains the information in the 7th previous check bit as well as the 6th data bit, so 1311i'・1
For example, if the healthy l evisoto of
Assuming 0%, burst errors with a length of 6 or less can be corrected.

[Explanation of effects]

As described above, according to the present invention, a decoding circuit dedicated to the IDROM is provided.
To prevent information from being easily deciphered and misused, and to provide an encoding method that does not correct errors, which is the original purpose of F1 encoding. can.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an apparatus according to an embodiment of the present invention. FIG. 2 is a circuit diagram of the signal processing section decoding circuit. FIG. 6 is a circuit diagram of the decoding circuit. 1... Antenna common area, 2-... Kesen area, 3...
- Base station arithmetic processing unit, 4... signal processing unit, 5...
Performance processing unit of mobile device, 6...ID ROM identification line number reading z'7 memory, 7...Base station, 8...Mobile device, 9...Shift register, 10...Switching Department, in
...Information source, 0...81 sent to the arithmetic processing unit
i-converted 11'4-report output signal, 11... switching unit, 1
2...Data shift register, 13...Check bit, 14...Syndrome (SYNDItOME)
) shift register, 16.19.20123.24
...Exclusive Nr1i logical sum circuit, 17.17'...Check bit (C elbow: c+(nrT), 18.18
'...Data (DATA), 21...Shift o
-M(sYNI)ROME) 22 ・”and(A
ND) times'l(+. Patent applicant: NEC Corporation:,, 7j- agent)
Patent attorney Naotaka Ide □

Claims (1)

[Claims] (1) includes a small number of base stations and a large number of mobile subscribers;
Each mobile subscriber has an identification code read-only memory in which a unique identification code is recorded, and a matching output is sent out when the ossified reduction code matches the readout output read from this memory. 91 communication between the base station and the mobile subscriber is recorded in the crystal-specific code read-only memory in a wireless communication system configured to perform code communication using an error correction method. The occupational code of the mobile subscriber is recorded using a code with check pits added according to the same rule as the error correction method described above, and the code read from this identification code read-only memory is recorded using the error correction method described above. An identification code encoding system for a wireless communication system, characterized in that the identification code encoding system is configured such that the read output is outputted via a decoding processing circuit of the system.