Kabushiki Kaisha Toshiba

Fujitsu Corporation

Ntt Mobile Communications Network, Inc.

Fujitsu Mobile Communications Limited

Naritoshi Saito

Mutsumu Serizawa

Kengo Kurose

Yutaka Asanuma

Miyuki Ogura

Yoshiyuki Kubo

Manabu Ishibe

Naohide Kushige

Yoshinori Nagao

Shouichi Oshima

Hironori Yoshida

A communication terminal apparatus includes: an assigning part configured to assign a usage right of a first subframe, from among a plurality of subframes included in a frame, to a base station, in a case where terminal-to-terminal communication is performed by transmission and reception of the frame directly with a different communication terminal apparatus, based on frequency information reported from the base station; and an acquiring part configured to acquire, during the terminal-to-terminal communication, information from the base station from the first subframe.

Communication terminal apparatus, communication control system, and communication control method

A wireless communication apparatus includes an acquisition unit, a calculation unit, a selection unit, and a notification unit. The acquisition unit acquires location information of a first terminal and a second terminal that perform terminal-to-terminal communication without using a base station. The calculation unit calculates a distance between the first and second terminals based on the acquired location information of the first and second terminals. The selection unit selects a frequency to be used for the terminal-to-terminal communication based on the distance calculated by the calculation unit. The notification unit notifies the first and second terminals of a start of the terminal-to-terminal communication and the selected frequency.

Frequency selection for device to device wireless communication

If a control unit detects that it is located outside the service area, searching for a base station on the basis of information stored in a first list storage area is conducted with a certain cycle by a first searching means and searching for a base station on the basis of information stored in a second list storage area is conducted in a gradually extended cycle, in accordance with the number of times Cs of searching for the base station, by a second searching means.

Mobile radio terminal

When a first base station serving a mobile communication terminal in a standby mode, a first neighbor list is acquired from the first base station and stored in a memory. If the serving base station is changed in a standby mode from the first base station to a second base station, a second neighbor list is acquired from the second base station. When the second base station is serving the mobile communication terminal in a standby mode, the communication quality between the mobile communication terminal and each second peripheral base station listed in the acquired second neighbor list, and between the terminal and each first peripheral base station listed in the stored first neighbor list. Based on the measurement results, a peripheral base station that satisfies a preset condition is selected as a hand-off destination candidate.

Mobile communication hand-off control system and unit

The terminal apparatus comprises first cell detecting means for receiving radio signals of the first radio scheme by using various kinds of PN offsets and for detecting receiving levels of the respective cells, and second cell detecting means for receiving radio signals of the second radio scheme by using the PN offsets based on a result of the detection of the first cell detecting means and for detecting receiving levels of the respective cells.

Mobile radio terminal apparatus

A radio communication system in which information of a unit length is constituted with a plurality of frames as a set and the information is transmitted/received between a base station and a mobile station. A control section of the base station decides, during a telephone communications, performed between the base station and the mobile station, when an instruction to switch the frequency to a second frequency is received from an upper order network via a transmission/reception section, a time interval for the telephone communication using the second frequency so as not to stride over a boundary of frame sets adjacent to each other.

Radio communication system and base station

A control unit controls a 1x RAKE receiving unit to intermittently receive a paging signal transmitted from a first base station in a first cycle, in the first cycle. The control unit also controls a 1xEV-DO RAKE receiving unit to intermittently receive a paging signal transmitted from a second base station in a second cycle, in a cycle which is a multiple of natural number n of the second cycle.

Transmission timing of the control signal is controlled such that each transmission timing differs between at least adjacent base stations. Thus, the mobile station can reproduce the control signal using only a predetermined spreading signal for the base station which transmits the control single. Therefore the time for reproducing process of the control signal can be reduced.

Control signal transmission timing control in radio communication system

A multiplier multiplies a baseband signal with a scramble code generated by a CPICH scramble code generator and an integrator integrates the result of the multiplication. A symbol selection control unit controls the integrator such that the integrator integrates each of two successive slots in which combinations of the symbols transmitted from two antennas of a base station are the same, in accordance with the information about the synchronous positions of the slots and frames. The result of the integration is delayed by a 1-symbol delay unit and then a code of a complex component is inverted by a complex conjugate unit. A multiplier multiplies the outputs of the integrator and complex conjugate unit, which are shaped in a complex number, to obtain an amount of phase rotation between the successive symbols, i.e. a frequency error.

Mobile radio terminal and automatic frequency control circuit

There is disclosed a spread spectrum wireless communications device capable of conducting a pilot search for a frequency different from the traffic-channel frequency used in a conversation while suppressing deterioration of voice quality. One frame is selected from every 5 frames such that the selected frames are not adjacent to each other. The reception frequency (searched frequency) is switched from frequency f1 used for communication to other frequency f2 during the period of any one of the selected frames. During the periods (e.g., N , N , and N ) of plural ones (e.g., 3 frames) of the frames in which f2 is being received, neighboring sets are searched for phases continuously.

Spread spectrum wireless communications device

There is provided a radio communication apparatus which is capable of both improving communication quality and reducing power consumption. An integrating clock generated by a clock generating section is supplied to each of integration damp filters contained in each data demodulator. Synchronizing with the integrating clock, each integration damp filter samples a despread receiving signal to integrate values of levels in each sampling timing for one symbol period. Based on an integrating method selecting signal supplied from a main control section, the clock generating section generates the integrating clock having the same frequency with a spread code rate (chip rate) or the integrating clock having the frequency of eight times of the spread code rate (chip rate).

Spread spectrum radio communication apparatus

A radio communication system which keeps to a minimum the number of slots which cannot be used due to interference from a neighboring base station, and which can increase the slot usage efficiency. A slot/frame setting unit for a base station extracts the slot/frame timing of a neighboring base station based on the reception output of a radio unit, and sets the communication frame by displacing it in such a way that two slots in the own base station do not coincide in time with a slot of the neighboring base station based on this timing. This setting ensures that there is always just a single slot which cannot be used when interference is detected.

Radio communication system

According to the system of the present invention, in a base station, a radio transmission characteristic of a forward link is estimated by a parameter estimating section 18b based on a receiving state of a radio signal arrived from a mobile station through a reverse link. Then, RAKE control data to be set to a RAKE receiver of the mobile station is generated based on the result of the estimation, and RAKE control data is notified to the mobile station. On the other hand, in the mobile station, RAKE control data is extracted by a RAKE control data extracting section. Then, a tap coefficient is initialized to be set to a transversal filter of the RAKE receiver based on RAKE control data.

Spread spectrum radio communication system

A spread spectrum radiocommunication device includes a plurality of digital data demodulators which are independently operated to track the paths of a multipath radio signal transmitted from a to-be-communicated device and PN code generators each of which has a ROM storing PN codes and which are respectively provided in the digital data demodulators. In a control section, a ROM address latched by an address latch circuit is monitored and a PN address relative value is generated, and the PN address relative value is added to a basic address generated from an address counter in an address adder and the added address is supplied to the PN code ROM to generate a PN code.

Growing community of inventors

Hino, Japan

Naritoshi Saito