Matsushita Electric Industrial Co., Ltd.

Nobuo Asano

Osamu Kato

Makoto Sasaki

Izumi Horikawa

Osama Kato

Mitsuru Uesugi

Minoru Okamoto

Toshihiro Ishikawa

Takayuki Nakano

Yoshiyuki Okubo

Yoshiharu Osaki

In an automobile on-board and/or portable telephone system capable of increasing the capacity of subscribers easily on the basis of changing of the information transmission bit rate, spread codes obtained by multiplying orthogonal spread codes (m in number) by a pseudo-random noise series are assigned to individual channels in the same cell in such a manner that the orthogonal spread codes are multiplied by some types of pseudo-random noise series having different phases, thereby making it possible to maintain the number of channels in the same cell at a value which is a multiple of the number of the orthogonal spread codes. Through this, in the case where the transmission bit rate is halved as compared to the presently existing rate in the future, assignment of spread codes which are increased in number to as large a value as necessary can be achieved and the subscriber's capacity can be increased within a range in which the necessary quality can be maintained even when link paths for m or more channels are set up in one cell from the viewpoint of Signal to Interference Ratio.

Automobile on-board and/or portable telephone system

An apparatus is provided that calculates a state at a time of starting an operation of a shift register that generates a PN code. The apparatus includes a system that obtains a parameter &ldquo;i&rdquo; that pertains to the state at the time of starting an operation, a system that obtains coefficients of a generator polynomial corresponding to the PN code, and a system that calculates the state at the time of starting an operation, based on the parameter &ldquo;i&rdquo; and the coefficients of the generator polynomial.

Method and apparatus for calculating a state of starting a PN code generating operation

A code reader reads code specification information stored in a code list. An interference level measurer measures the interference level of a received signal despread with the code specification information read by the code reader. A threshold selector selects a code specification information corresponding to an interference level smaller than a preset threshold and stores the selected code specification information in a code candidate list. A code determiner determines the code specification information of a base station from the selected code specification information. When a new base station is added, a base station code may be automatically determined without needing a theoretical design for assigning codes to all base stations.

CDMA base station apparatus and code assignment method

A mobile radio system includes a base station and a plurality of mobile radio apparatuses, with each mobile radio apparatus including a control CPU for controlling the mobile radio apparatus and monitoring the state of the hardware of the mobile radio apparatus, a transmitter unit for transmitting data in the form of radio waves, and a CPU monitor unit. The control CPU regularly monitors and checks for any abnormalities in the hardware of the mobile radio apparatus, and the CPU monitor unit regularly monitors and checks for any abnormalities in the control CPU. If there is an abnormality, a disabled transmission out put acceptance signal is supplied to the transmitter unit to inhibit or suppress the output of radio waves thereby avoiding interference to the system caused by unnecessary radio wave transmission from an abnormal mobile radio apparatus.

Mobile radio system with control over radio wave output if a malfunction is detected

In a PN code generating apparatus, a code of the predetermined number of stages is generated using primitive polynomial G(x), then the code content of each stage is shifted to the next stage. And a state setting section obtains a code state of the PN code generating section after shifted the specific times from a code state of the PN code generating apparatus at a certain time, based on x,modG(x) as the number of shift times is i.

PN code generating apparatus and mobile radio communication system

A receiving portion of a radio communication device includes a circuit periodically moving into a sleep mode of operation. The circuit periodically moves out of the sleep mode of operation in response to a re-activation signal. A first clock signal is generated. Clock pulses in the first clock signal are counted. The re-activation signal is generated each time the number of the counted clock pulses in the first clock signal reaches an updatable number. A second clock signal is generated which has a frequency higher than a frequency of the first clock signal. Clock pulses in the second clock signal are counted during every time interval determined by the first clock signal. An error of the frequency of the first clock signal with respect to the frequency of the second clock signal is calculated on the basis of a result of the counting of clock pulses in the second clock signal. The updatable number is set in response to the calculated error of the frequency of the first clock signal.

Receiving portion of radio communication device

A base station includes an incoming call terminal identification message generating portion When the base station transmits an incoming call message to a terminal, an incoming call terminal identification message useful for only the incoming call terminal, for example a message such as ID number information peculiar to the terminal, is inserted in the head of a slot assigned to the terminal and is transmitted. When the incoming call terminal detects the incoming call terminal identification message, the terminal receives a regular incoming call message transmitted thereafter. When the terminal cannot detect the incoming call terminal identification message, the terminal judges that the message is not directed to a call to its own terminal and immediately stops monitoring of the slot at this time.

Radio communication apparatus which includes a base station and

A mobile radio system includes a base station and a plurality of mobile radio apparatuses, with each mobile radio apparatus including a control CPU for controlling the mobile radio apparatus and monitoring the state of the hardware of the mobile radio apparatus, a transmitter unit for transmitting data in the form of radio waves, and a CPU monitor unit. The control CPU regularly monitors and checks for any abnormalities in the hardware of the mobile radio apparatus, the CPU monitor unit regularly monitors and checks for any abnormalities in the control CPU. If there is an abnormality, a disabled transmission output acceptance signal is supplied to the transmitter unit to inhibit or suppress the output of radio waves, thereby avoiding interference to the system caused by unnecessary radio wave transmission from an abnormal mobile radio apparatus.

Mobile radio system with control over radio wave output if a malfunction

An arithmetic apparatus in which while data read out of a memory is shifted by means of a barrel shifter by a shift bit number designated by data standing for an output signal of an inverter, data standing for an output signal of the barrel shifter is inputted to a shift register to thereby perform Viterbi decoding at a high speed.

Arithmetic apparatus for carrying out viterbi decoding at a high speed

In an automobile on-board and/or portable telephone system capable of increasing the capacity of subscribers easily on the basis of changing of information transmission bit rate, spread codes obtained by multiplying orthogonal spread codes (m in number) by a pseudo-random noise series are assigned to individual channels in the same cell in such a manner that the orthogonal spread codes are multiplied by some types of pseudo-random noise series having different phases, thereby making it possible to maintain the number of channels in the same cell at a value which is a multiple of the number of the orthogonal spread codes. Through this, in the case where the transmission bit rate is halved as compared to the presently existing rate in the future, assignment of spread codes which are increased in number to as large a value as necessary can be achieved and the subscriber's capacity can be increased within a range in which the necessary quality can be maintained even when link paths for m or more channels are set up in one cell from the viewpoint of Signal to Interference Ratio.

A CDMA system in which carriers are segregated according to the self-sacrifice of a mobile station resulting in no communication quality deterioration due to shadowing The mobile station detects a base station which causes a sudden increase in the reception power of the mobile station, and generates self-sacrifice information and transmits the information to the base station communicating with the mobile station. The informed base station detects the self-sacrifice information transmitted from the mobile station and informs mobile communication control equipment. The mobile communication control equipment designates a carrier which is prohibited from future use and the concerned base station. The concerned base station discontinues use of the designated carrier.

Code division multiple access communication system

In variable bit rate communications in which the information rate changes at B/2.sup.n (where n is 0 or a positive integer) in each frame when the maximum information rate is B, at the transmitter side, information data is convolution coded in order to carry out an error correction of the information data, and when n.gtoreq.1, coded data is repeatedly transmitted by (2.sup.n -1) times. At the receiver side, the information rate is detected from the transmission data that has been received, and when carrying out Viterbi decoding, an information rate is estimated by utilizing the repetition characteristics of the data, so that the coded data is Viterbi decoded for only the estimated bit rate, to thereby restrict an increase in the power consumption of mobile terminal units that are driven by batteries.

Variable rate communication method and a variable rate communication

A mobile communication unit which can perform a high-bit rate information transmission by allocating a plurality of channel numbers to a user who carries out a high-bit rate communication. The mobile communication unit includes a set of units at the transmitter side 21 and a set of units at the receiver side 22, to carry out communications by allocating spread codes to channels within the same cell. A plurality of channel numbers are allocated to one user. The transmitter side units include the separating unit 23 for separating the user information, the spread modulator 30 for spread processing the separated information by using the spread codes corresponding to the respective channel numbers, and the combining unit 31 for combining the diffused information and outputting the combined information to the receiver side unit. The receiver side units include the despreader 32 for despread the diffused information by using the spread codes of the respective channel numbers allocated to the user, and the multiplexing unit 33 for combining the despreaded information of the plurality of channels. Thus, a high-bit rate transmission service is provided.

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Yokohama, Japan

Nobuo Asano