Nippon Telegraph and Telephone Corporation

Satoshi Kurosaki

Yasuo Suzuki

Yusuke Asai

Takatoshi Sugiyama

Naoki Kita

Atsushi Ota

Kota Ito

Satoru Aikawa

Kazuto Goto

Yuji Nakayama

Daisei Uchida

Masahiro Umehira

Yutaka Imaizumi

Masahiko Itoh

A receiving station performs first signal detection processing on a received radio signal, performs a retransmission request to a transmitting station in a case in which a code error is detected in a detected radio packet for user data, and enqueues the radio packet in a reception buffer in a case in which no code error is detected. In parallel with the first signal detection processing, the receiving station performs second signal detection processing on the received signal with a longer processing delay than that of the first signal detection processing, and in a case in which no code error is detected in the detected radio packet for user data, the receiving station enqueues the radio packet in the reception buffer. The receiving station outputs, at a predetermined timing, the radio packet for user data with no code error detected, the radio packet being enqueued in the reception buffer.

Retransmission control method

An OFDM signal communication system used in broadband mobile communication, achieves stable operation under severe frequency selective fading environments, giving high quality. The OFDM signal communication system which transmits OFDM signals over the same radio frequency from N transmitting antennas, has an inverse matrix computer for computing an N&#xd7;N inverse matrix constituted by propagation coefficients for respective propagation paths between each of N transmitting antennas and each of N receiving antennas, and a subcarrier demodulator which separates the signals of the respective propagation paths, based on the obtained inverse matrix.

OFDM signal communication system, OFDM signal transmitting device and OFDM signal receiving device

In a wireless access system which uses the sector antenna of a radio base station to transmit an access channel to and receive an access channel from a radio terminal in each frame, and which switches the sector at each frame, the sector ID s is set in a specific functional relation to the access channel ID a, and a radio terminal which communicates with a radio base station transmits and receives in accordance with the access channel ID a without knowing the sector ID s.

Wireless access system

Growing community of inventors

Yokosuka, Japan

Satoshi Kurosaki