Ntt Docomo, Inc.

Ntt Mobile Communications Network, Inc.

Yutaka Ohto

Masafumi Masuda

Takehiro Nakamura

Yasuhiro Kato

Seizo Onoe

Tomoyuki Ohya

Kazunori Obata

Takashi Ueda

Akihiro Maebara

Kota Fujimura

Shinji Ueda

Yoshinobu Nakamura

The object of the invention is to prevent reduction of the system capacity caused by the use of a channelization code belonging to the secondary scrambling code. Instead of trying to select a channelization code belonging to each of the primary and secondary scrambling codes for one cell in a conventional manner, selection of a channelization code belonging to the primary scrambling code is tried sequentially for a plurality of cells (S, S). If the selection of the code has been failed, it is determined whether selection is tried again under a different condition (S). Then, when trying again, selection of a channelization code belonging to the secondary scrambling code is tried sequentially for the plurality of cells (S, S).

Radio control device and method of selecting spread code

There is provided a neighbor cell notifying apparatus capable of implementing more efficient notification to a mobile station within a range that can be notified of and monitored, when the mobile station in communication using a plurality of cells is notified of neighbor cell information. This neighbor cell notifying apparatus includes a cell information extracting part for extracting neighbor cell information items for specifying respective neighbor cells corresponding to each of the cells; a cell rank determining part for, based on the neighbor cell information items extracted, determining ranks of neighbor cell information items that the mobile station is to be notified of, in favor of neighbor cell information items about neighbor cells common to the cells; and a cell information notifying part for notifying the mobile station of a predetermined number of neighbor cell information items among the neighbor cell information items on the basis of the ranks determined.

Neighbor cell notifying apparatus and neighbor cell notifying method

Disclosed is a mobile communication system whereby, to reduce the connection time, a mobile station closely located to a base wireless station is permitted to continue to use a common channel for exchanging signals, and to suppress an increase in interference, an individual channel is set for a mobile station located near the edge of a cell, and to obtain a stabilized communication quality and to prevent an increase in the connection time, the probability that the transmission power will reach an upper limit is reduced. When communication between a mobile station and a wireless base station is started, the wireless base station measures the transmission power and the communication quality in the communication with the mobile station and the utilization ratio for a common channel, and compares the obtained values with predetermined threshold values. When the obtained values are lower than the threshold values, the wireless base station continues to use the common channel for signal transmission/reception. On the other hand, when the obtained values exceed the threshold values, the wireless base station sets an individual channel and sets a wireless channel so as to be capable of the continued use of the individual channel for the exchange of signals.

Wireless channel setting method for mobile communication system and mobile communication control apparatus

Speech information freeze-out control method and equipment in mobile

Growing community of inventors

Yokohama, Japan

Yutaka Ohto