Sony Corporation

Matsushita Electric Industrial Co., Ltd.

Sony Ericsson Mobile Communications Japan, Inc.

Ntt Mobile Communications Network, Inc.

Matsushita Communication Industrial Co., Ltd.

Sony Mobile Communications Inc.

Taku Nagase

Noboru Oki

Katsutoshi Itoh

Makoto Sasaki

Makoto Natori

Yasuyoshi Kuwazoe

Masanori Sato

Osamu Kato

Kazuyuki Miya

Mitsuru Uesugi

Daisuke Yamada

Akihiro Higashi

Takashi Kitade

Kazuhiko Terashima

Tadashi Matsumoto

Takashi Izumi

Roland Go

Hiroaki Nagaoka

Gen-Ichiro Ota

Noburu Oki

A communication terminal device includes: a turbo encoder that performs two systems of convolutional encoding with respect to input data and preforms turbo encoding processing with in-block interleave preformed on one of the two systems using an internal interleaver. Rate matching (puncturing) units which puncture an output of the turbo encoder based on a predetermined rate matching algorithm and interleavers, which change the output of the turbo encoder such that a puncturing cycle based on the rate matching algorithm of the rate matching units is changed. Accordingly, turbo code performance is improved.

Method and apparatus for performing turbo encoding in a 3GPP mobile communication system

A wireless communication system wherein frame data is encoded with an outer code and then divided into predetermined number of blocks which are encoded with an inner code into transmission data. In a receiver, a decoder decodes the received transmission data in accordance with the inner code, a retransmission order determining unit determines whether to perform a retransmission order in units of blocks based on the likelihood information (decoded soft-decision value). At this time, the retransmission order determining unit inhibits the retransmission order for the block if the number of inner-code errors in a frame consisting of predetermined number of blocks stays within a limit of what the outer code can correct at a decoder and determines that a retransmission is necessary if the number of inner-code errors in the frame exceeds the limit.

Retransmission ordering method, wireless communication system, receiver and transmitter

The present invention provides a receiving apparatus and method in which frequency of calculation such as weighting multiplication and memory capacity of a frame buffer can be reduced. To this end, reference phase information and data are separated by a reference phase inverse spreading unit () and a data portion inverse spreading unit (), respectively. A weighting coefficient calculating unit () calculates weighting coefficients based on SNR values as transmission line information from an SNR calculating unit () and sends calculated weighting coefficients to a multiplier (), where phase correction values based on the reference phase information are multiplied by the weighting coefficients to be correction coefficients. A multiplier () multiplies reception data from the data portion inverse speading unit () by the correction coefficients, and output data from the multiplier () is restricted in bit width by the bit width restricting unit () The output data which is restricted in bit width from a coherent receiving unit () and that of a coherent receiving unit () are added by an adder (), and the output data from the adder () is sent to a frame buffer () to be stored. Then, the output data from the frame buffer () is sent to a soft decision input error correcting unit ().

Receiving apparatus and receiving method

Disclosed is a method and an apparatus for controlling transmission electric power capable of minimizing a decrease in the amount of maximum transmission electric power without degrading an adjacent channel leakage power ratio when code-multiplexing additional control information with data and main control information. A mobile device checks values of gain factors &#x3b2;d and &#x3b2;c when performing code multiplexing to transmit signals from channels DPDCH to transmit data, DPCCH to transmit main control information, and HS-DPCCH to transmit additional control information. A maximum transmission electric power is decreased at a plurality of levels based on the check result and a ratio (&#x394;hs) between the gain factors &#x3b2;c and &#x3b2;hs. It may be preferable to check the presence or absence of transmission data instead of the gain factor &#x3b2;d. In this case, when no transmission data is available, the maximum transmission electric power is decreased at a plurality of levels based on &#x394;hs. When transmission data is available, the maximum transmission electric power is decreased at a plurality of levels based on the gain factor &#x3b2;c and &#x394;hs.

Transmission power control method and device

Provides a normalizing apparatus that normalizes input signals to a turbo decoder without significantly increasing a size of a circuit. An input signal buffer () obtains a sum S for N pieces of input signal data I(i). An input data averaging part () obtains an average A by dividing the sum S by the number of data N. A divider () obtains normalized data I(i)/A by dividing the input signals I(i) by the average A. A weighting part () multiplies the normalized data I(i)/A with a weighting coefficient &#x3b1;, which is determined based on a ratio of a number of input data and a number of output data in rate matching. As a result, the normalization is made possible. Because a signal receiving quality does not need to be determined, an increase in circuit size is inhibited.

Normalizing device and method, program, recording medium on which the program is recorded and communication terminal for normalizing data

A data reception device is provided with: a puncture rate detection element to detect the puncture rate of received data, an interpolation element to interpolate bits decimated at the detected puncture rate, a deinterleaving element to restore interleaved data to the original arrangement, and a turbo-decoding element, while variably setting the length of the learning interval according to the puncture rate detected by the puncture rate detection element, to input sliding window data and the data of the above learning interval following the data of the sliding window to the data processed by the interpolation element and deinterleaving element, and to perform recursive operations to decode the data of the sliding window. The valid received signal contained in the learning interval can be maintained approximately constant even if the puncture rate changes.

Turbo-code decoding using variably set learning interval and sliding window

A decoding apparatus, decoding method, data-receiving apparatus, and a data-receiving method for performing a maximum-likelihood decoding process based on a Viterbi algorithm on a data train completing a convolution-encoding process. The apparatus includes a computation device for performing a trellis computation for decoding a data train completing the convolution-encoding process. The decoding apparatus further includes a control device for controlling the trellis computation to be carried out by the computation device with processing timings in processing units each corresponding to a process carried out on n bits of pre-encoding data, in which each of the processing units is parallel processing carried out on computation results obtained for 2states with one of the processing timings immediately preceding a present one of the processing timings to find the computation results with the present processing timing for the 2states.

Decoding apparatus, decoding method, data-receiving apparatus and data-receiving method

Removing adverse effects in case error detection using error detection codes cannot be performed correctly, and improving the data transmission efficiency. The turbo decodercompares data which is decoded this time with data which is decoded previous time, both of which are decoded in repetitive decoding processing, to obtain discord number information indicative of the number of discordant sign bits, and sends the information to a terminal I/F unitand a packet flow retransmission controlling unit. Even though it is determined that error detection result from a CRC recalculating unitshows that there exists no bit error, in case the number of discordant sign bits is larger than a predetermined threshold value, it is determined that there is generated error. And, a packet flow retransmission controlling unitsends a signal requesting retransmission of data. Furthermore, data amount to be retransmitted is varied in accordance with the number of discordant sign bits to improve the data transmission efficiency.

Decoding apparatus and decoding method, and data receiving apparatus and data receiving method

The spread spectrum communication system based on the CDMA-FDD system in which two or more carrier frequencies can be selectively used in the present invention is equipped with the section that carries out handover between base stations with the same carrier frequency switched by a spreading code from a carrier frequency used in communication and the section that switches carrier frequencies within the handover base station after handover between base stations is completed. This allows the mobile station to carry out handover between base stations with different frequencies without the mobile station transmitting/receiving two or more carrier frequencies simultaneously.

Spread spectrum communication method

The present invention relates to a code generating method for combining an orthogonal code for CDMA having a specific spreading factor and its polarity inverted spreading code to generate another spreading code having a larger spreading factor than that of the spreading code. And the present invention relates to a code selecting method for combining an orthogonal code for CDMA having a specific spreading factor and its polarity inverted spreading code to generate another spreading code having a larger spreading factor than that of the spreading code, then to assign the generated orthogonal code for a user in order of users having an orthogonal code of small spreading factor.

Code generating method and code selecting method

A spread spectrum portable telephone apparatus operates with long wait times and with little battery depletion while waiting. A mobile unit receiver receives and detects radio signals, analog-to-digital (AD) converts the detected reception signals, waveform-shapes the converted signals, despreads and decodes the waveform-shaped signals with a spread signal, frame-resolves the decoded signals, and extracts reception date from the frame-resolved signals. A data receiver is included which has, for both a pager channel and a communications channel, a narrow band AD converter circuit, a narrow band reception filter for waveform-shaping the AD converted signals, and a correlator which despreads and decodes the waveform-shaped signal using a spread code generated by a low speed spread code generator circuit. When waiting, calls to the apparatus are waited for with the power turned on only to the paging channel data receiver.

CDMA spread spectrum mobile phone

A search unit of a receiver synchronizer includes a search PN signal generator for generating PN signals for all PN phases in order to search the maximum power path; a search correlation unit which outputs a correlation value from sampling data and the PN signal; a data buffer for storing the correlation value; a path search unit for controlling a search the path using the correlation value received from the data buffer; a PN signal generator for outputting a PN signal to a DLL and a data demodulation correlation device; and a DLL switch for switching the PN phase to the phase of the maximum power path by controlling the PN signal generator as a result of the search for the path. The PN phase of the PN signal output to the DLL is constantly maintained in synchronization with the phase of the maximum power path.

Synchronizer for receiver of spread spectrum communication apparatus

A base station of a CDMA communication system includes a transmission de-correlator for eliminating interferences between communication channels of a downlink. The transmission de-correlator has a memory storing a set of data representative of the products of transmission information bits for the respective channels, and the sums of the products of the spread code data sequences for the respective channels, and the elements of an inverse matrix with respect to a predetermined matrix of a cross-correlation between the spread code data sequences for the respective channels. The sums correspond to additions of the products along a direction of columns or to additions of the products along a direction of rows of the inverse matrix. A counting device is operative for causing the memory to sequentially output the data therefrom. An adder serves to calculate a sum of the data outputted from the memory.

Transmission de-correlator for eliminating interference in a CDMA

When a power supply of a mobile radio apparatus is turned on, a power supply change-over switch of a power supply control unit is changed over to the side of a pager unit to turn on only a power supply of the pager unit, so that a pager network which does not require position registration is utilized to perform intermittent receiving operation with low power consumption. When there is an incoming call to the pager unit, a CPU of the power supply control unit receives an incoming control signal from a pager decoding circuit and changes over the power supply change-over switch to the side of a radio-telephone line terminal unit to turn on the radio telephone line terminal unit and turn off the pager unit. The CPU sends a control signal to a timing control circuit of the radio-telephone line terminal unit so that the position registration is performed by utilizing a mobile radio network and an operation mode of the mobile radio apparatus proceeds to a usual talking mode. After a pager calling has been performed in a calling side, the mobile radio apparatus is called by the portable telephone number and talking is then is made. When the talking has been finished, the CPU receives a control signal from the timing control circuit and changes over the power supply change-over switch to the side of the pager unit again to turn on the pager unit to enter a waiting state for reception.

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Tokyo, Japan

Taku Nagase