Matsushita Electric Industrial Co., Ltd.

Minako Ide

Katsuhiko Hiramatsu

Hideki Yukitomo

Sadaki Futagi

Keiji Takakusaki

Keiji Takausaki

A frequency offset may be determined by detecting phase information for both a one-symbol difference and a two-symbol difference of a received known signal. Half a value representing the phase information detected for the two-symbol difference is averaged, for a particular interval, with a value representing the phase information detected for the one-symbol difference. The frequency offset is determined from the average.

Frequency offset quantity detecting apparatus

The present invention relates to a method for adaptively controlling a transmission radiation pattern. Radio signals coming through a plurality of paths are received and demodulated for each path. The received level or received quality of each demodulated signal is compared to each other to select a signal with the highest level or most excellent quality. A path corresponding to a selected path is set at a path for transmission. When a plurality of signals each with an almost equal level or received quality exists in signals demodulated for each path, a history of transmission power control command (TPC) transmitted from a communication partner is referred. In other words, the reception condition in a communication partner is checked. Thereby, it is judged whether or not the currently selected path is appropriate as the path for transmission.

Directivity control type communication apparatus and adaptive array antenna apparatus

Method of directive transmission and directivity-controlled communication device

A multiplication circuit multiplies signals, which are subjected to variable directional transmission, by weighting factors with respect to the respective antennas to , and outputs the resultant to combining circuits to , respectively. The signals input to the combining circuit are combined and radio modulated by a radio section , and transmitted from the antenna . Whereby, in a case where variable directional transmission is performed with respect to only some terminal apparatuses, signals, which are subjected to no variable directional transmission, can be transmitted after spreading them from the respective antennas of an array antenna.

Base station device and transmission method

A diversity receiver estimates a reception weight sing signals received at a plurality of antennas, a target pattern former forms a target radiation pattern based on the estimated reception weight, a transmission pattern former forms a transmission radiation pattern with a transmission weight using an arbitrary transmission weight as an initial value, a controller limits an angle range in which formation of the target radiation pattern and formation of the transmission radiation pattern are executed, an error detector detects an error between the target radiation pattern and the transmission radiation pattern, and subjects the detected error to logarithmic transformation, an updator updates the transmission weight so as to reduce the error subjected to logarithmic transformation, and a directivity former provides a transmission signal with a directivity according to the transmission radiation pattern formed using an updated transmission weight.

Adaptive directivity transmission device and method

When carrying out directive reception using an adaptive array antenna apparatus, a plurality of diversity reception circuits which differ in communication environment follow-up performance are used for reception and the reception output with the best reception quality is selected. The environment follow-up performance of the other non-selected diversity reception circuits is dynamically changed, preferably every time a selection is made by a selector based on the environment follow-up performance of a selected diversity reception circuit.

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Yokohama, Japan

Minako Ide