Nec Corporation

Sei Hirade

Motoya Iwasaki

Osami Nishimura

Yukio Haseba

A wireless communication apparatus with a plurality of antennas which receive a wireless reception signal from a secondary communication apparatus, and a combiner which combines signals from the plurality of antennas to form a combined signal or selects one of the signals from the plurality of antennas. A wireless communication apparatus with a plurality of antennas which transmits a wireless transmission signal to a secondary communication apparatus and a divider which divides a transmission signal into plurality of transmission signals to be transmitted by the plurality antennas or selects one of the plurality of antennas to transmit the transmission signal.

Wireless diversity receiver using a combiner with control weights that are based on reported transmission power

A path protection method for a CDMA reception apparatus is disclosed, which obtains correlation value levels while shifting the despreading timing of reception data little by little, searches for optimal reception timings, outputs a plurality of finger path timings, with respect to the reception data, as reception timings at which reception should be performed, and despreads the respective paths, thereby performing RAKE combining. If all protection paths are in the forward protection state upon execution of path backward protection and forward protection, a protection path with the lowest level is deleted, and a search path having the highest level among paths which are equal to or more than a threshold and detected by a searcher is registered in the deleted portion, thereby allowing assignment of a newly detected path even in the absence of a protection path space.

CDMA path protection method based on path protection information

A delay profile calculator comprises dedicated correlators and shared correlators, and calculates the numbers of shared correlators allocated to respective users from the number of subscribing users and the total number of shared correlators. If the number of subscribing users is small, i.e., if there are excessive correlators, then it is possible to increase the number of correlators allocated to one user.

Correlator allocation control process for allocating correlator group as divided into shared correlators and dedicated correlators

A CDMA receiving apparatus includes a searcher section, a finger section, a RAKE synthesizing section and a decoding section. The searcher section has a protection path memory, generates a delay profile from a reception signal, and finds peaks from the delay profile based on a variable peak level reference threshold value and a variable noise level reference threshold value which are determined based on the delay profile. Also, the searcher section reads out protection path data in a previous cycle from the protection path memory, and determines timings of valid paths based on timing of the found peaks and protection path timings of the read out protection path data. The finger section detects a signal from the reception signal for every path in response to the valid path timings. The RAKE synthesizing section carries out RAKE synthesis to the detected signals to produce a RAKE synthesis signal. The decoding section decodes the RAKE synthesis signal.

Method of detecting path timings and CDMA receiving apparatus using the same

A path searching apparatus which is used in a base station apparatus according to the CDMA (Code Division Multiple Access) systems for increasing the accuracy for path detection depending on the number of communication channels to be processed. The path searching apparatus has a path searcher for generating a delay profile through to a path searching process composed of a plurality of processing units, an interpolation information storage for storing interpolation information indicative of whether an interpolation process for reducing a chip interval is to be performed or not before and after each of the processing units, an interpolation position processing control for enabling the path searcher to perform an interpolation process before and after each of the processing units based on the interpolation information stored in the interpolation information storage according to the number of the communication channels to be processed, and a path detector for detecting a reception path based on the delay profile generated by the path searcher.

Path searching method and device

In a frequency sharing method, IS-95 base station apparatuses and W-CDMA base station apparatuses are arranged in a one-to-one correspondence. The first base station transmission power value of the first base station apparatus is obtained in each frequency band in the IS-95 scheme. The second base station transmission power value of the second base station apparatus adjacent to the first base station apparatus is obtained. Whether there is a frequency band in the IS-95 scheme in which the sum of the first and second base station transmission power values is a predetermined threshold or more is determined. When there is a frequency band in the IS-95 scheme in which the sum is the predetermined threshold or more, a frequency handoff is performed to switch a communication channel in the IS-95 scheme which is using the frequency band in which the sum is not less than the predetermined threshold to another frequency band in the IS-95 scheme. An IS-95 base station apparatus, a mobile communication system, and a W-CDMA base station apparatus are also disclosed.

IS-95 base station apparatus, W-CDMA base station apparatus, mobile communication system, and frequency sharing method

Each mobile terminal comprises a memory which memorizes whether or not a last call end state is a squelch end and which memorizes, in case where the last call end state memorized in the memory is the squelch end, a random minimum value greater than that in case where the last call end state memorized in the memory is not the squelch end, a probability generating section, and a call setup request section responsive to a call setup request for detecting a call regulation value from a call regulation signal, supplying the random minimum value memorized in the memory to the probability generating section to make the probability generating section generate as a call setup request probability one of a plurality of random numbers within a range between the random minimum value and a random maximum value, and transmitting a call setup signal to a base station in case where the call setup request probability is greater than the call regulation value.

Mobile communication system capable of quickly responding a call setup request even during control of call congestion if a last call has been interrupted by a squelch function

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Tokyo, Japan

Sei Hirade