Abstract: A wireless communications system for performing data communications between a data transmission side wireless communications device and a data receiving side wireless communications device. In the system, random back-off access control is performed until a connection is established between the data transmission side wireless communications device and the data receiving side wireless communications device. Then, after the connection is established, asymmetric IFS access control is performed.

Abstract: In a data transfer system in which wireless data transmission is carried out between a first device and a second device that each has a UWB wireless device, the data transfer system includes a ranging unit that is provided in the UWB wireless device of at least one of the first and second devices and measures a distance to the other of the first and second devices; a distance determination unit that determines, based on a measurement result by the ranging unit, whether or not the distance between the first and second devices has been within such a predetermined range that a predetermined transmission rate and a predetermined transmission quality are obtained by UWB communication; and a data transfer unit that executes data transmission between the first and second devices in response to a determination by the distance determination unit that the distance between the first and second devices has been within the predetermined range.

Abstract: A radio communication method for exchanging information between a base station and a terminal station. The method includes: communicating the information between the base station and the terminal station by multi-carrier signals by OFDM modulation scheme including plural subcarriers within a bandwidth, communicating control signals in addition to the information between the base station and the terminal station, and wherein part of the control signals addressed to the terminal station from the base station is transmitted by one or more specific subcarriers in the bandwidth for the multi-carrier signals.

Abstract: A wireless communications system for performing data communications between a data transmission side wireless communications device and a data receiving side wireless communications device. In the system, random back-off access control is performed until a connection is established between the data transmission side wireless communications device and the data receiving side wireless communications device. Then, after the connection is established, asymmetric IFS access control is performed.

Abstract: In a data transfer system in which wireless data transmission is carried out between a first device and a second device that each has a UWB wireless device, the data transfer system includes a ranging unit that is provided in the UWB wireless device of at least one of the first and second devices and measures a distance to the other of the first and second devices; a distance determination unit that determines, based on a measurement result by the ranging unit, whether or not the distance between the first and second devices has been within such a predetermined range that a predetermined transmission rate and a predetermined transmission quality are obtained by UWB communication; and a data transfer unit that executes data transmission between the first and second devices in response to a determination by the distance determination unit that the distance between the first and second devices has been within the predetermined range.

Abstract: A wireless transmission apparatus and a wireless transmission method capable of performing simple transmission control, in which an information transmission flow control method, instead of reporting vacant-buffer information from a receiving destination apparatus, an information transmission-source apparatus permits the transmission of a packet up to a predetermined transmission window size from the packet for which acknowledgement has not been received from an information receiving destination, and the transmission of a packet exceeding that transmission window size is inhibited. As a result, if the packet is within that transmission window size, even if the information receiving destination has not confirmed the reception of the acknowledgement (ACK) information, the packet is transmitted unconditionally.

Abstract: A communication apparatus which is in a wireless network is characterized by comprising a communication means transmitting information among the other communication devices, a means receiving priority order information representing stand-by times different in each communication device from the control station and setting communication devices as control station candidates in a memory, and a means performing communication control as a control station in the wireless network when the stand-by time elapses.

Abstract: A communication apparatus which is in a wireless network is characterized by comprising a communication means transmitting information among the other communication devices, a means receiving priority order information representing stand-by times different in each communication device from the control station and setting communication devices as control station candidates in a memory, and a means performing communication control as a control station in the wireless network when the stand-by time elapses.

Abstract: To provide a radio transmission method and a radio transmission apparatus capable of performing a highly-efficient radio transmission depending on the number of communicating stations, a predetermined frame period is prescribed, a management information transmitting field being provided within the frame period, a station sync transmit/receive interval being provided within the management information transmitting field and an arbitrary communicating station being designated to transmit a station sync at plural frame period intervals during the station sync transmit/receive interval. Thus even if only the station sync transmitting area corresponding to the number which is less than the number of communicating stations forming a network exists within one frame, the station sync can be transmitted and received.

Abstract: A communication apparatus which is in a wireless network is characterized by comprising a communication means transmitting information among the other communication devices, a means receiving priority order information representing stand-by times different in each communication device from the control station and setting communication devices as control station candidates in a memory, and a means performing communication control as a control station in the wireless network when the stand-by time elapses.

Abstract: A communication apparatus which is in a wireless network is characterized by comprising a communication means transmitting information among the other communication devices, a means receiving priority order information representing stand-by times different in each communication device from the control station and setting communication devices as control station candidates in a memory, and a means performing communication control as a control station in the wireless network when the stand-by time elapses.

Abstract: An offset value corresponding to the difference between counter values of cycle time counters in two buses is obtained and stored, so that the buses are connected, the value of a first cycle time counter is compensated for buy an offset value. The counter value of the first cycle time counter is compared with the counter value of a second cycle time counter, and a time stamp of data is changed corresponding to the offset value.

Abstract: A communication apparatus which is in a wireless network is characterized by comprising a communication means transmitting information among the other communication devices, a means receiving priority order information representing stand-by times different in each communication device from the control station and setting communication devices as control station candidates in a memory, and a means performing communication control as a control station in the wireless network when the stand-by time elapses.

Abstract: A radio communication system where a connection between a controlled radio communication apparatus and a controlling radio communication apparatus is registered.

Abstract: In order to define and validate a station in a same network easily by specifying a unique network ID in a wireless network system, by using the validation information including the unique network ID in the wireless network system, it is designed to execute, as required, a process of subscribing and connecting to an existing wireless network system in the own station, a process of building up a new wireless network system starting from the own station, a process of transmitting validation information to other station in non-registered state of network ID, as the own station subscribed to the existing wireless network system working as the control station, and a process of removing the station subscribed to the existing wireless network system from the network.

Abstract: A radio communication method or system for transmitting part of the control signal addressed to a terminal station from a base station by means of a narrow-band carrier which is narrower than the band of multi-carrier signal and is arranged in the vicinity of the frequency band used for information transmission, in the case where a plurality of frequency bands for information transmission exist continuously. It may be modified such that part of the control signal addressed to the terminal station, which is transmitted from the base station, is transmitted by means of one or more subcarriers in the band of the multi-carrier signal. A radio communication method for exchanging information between a base station and a terminal station in the frame period by means of multi-carrier signals due to OFDM modulation scheme, in which the transmission of part of the control signal addressed from the base station to the terminal station is accomplished by means of the specific position in the frame period.

Abstract: Whether a communication is possible among nodes which transmit data in a wireless manner is discriminated and the nodes which can mutually communicate thereamong are set to the same group. In each node, if a node which can communicate with two or more groups exists, the node which can communicate among the groups is set to a bridge connecting the different groups. In case of communicating with the nodes among the different groups, a communication is performed via the node that has been set as a bridge.

Abstract: A wireless transmission apparatus and a wireless transmission method capable of performing simple transmission control are provided. As an information transmission flow control method, instead of reporting vacant-buffer information from a receiving destination apparatus, an information transmission-source apparatus permits the transmission of a packet up to a predetermined transmission window size from the packet for which acknowledgement has not been received from an information receiving destination, and the transmission of a packet exceeding that transmission window size is inhibited. As a result, if the packet is within that transmission window size, even if the information receiving destination has not confirmed the reception of the ACK information, the packet is transmitted unconditionally. Furthermore, a transmission pointer and an ACK receiving pointer are provided, and even if acknowledgement is not received, control is performed using that transmission window size in which transmission is possible.

Abstract: A communication apparatus which is in a wireless network is characterized by comprising a communication means transmitting information among the other communication devices, a means receiving priority order information representing stand-by times different in each communication device from the control station and setting communication devices as control station candidates in a memory, and a means performing communication control as a control station in the wireless network when the stand-by time elapses.

Abstract: A communication system capable of avoiding crosstalk with a simple structure. By assigning the same identification-number data to a transmitter and a receiver, performing the logical operation for the identification-number data with the logical operation circuit of the transmitter and the receiver, and detecting errors in the operation results by using error detection circuit, it is possible to perform enciphering and certifying without increasing communications traffic and thus avoid crosstalk with a simple structure because it is unnecessary to add and transmit the identification-number data.