Abstract: A transparent conductive film is disposed on the light-transmitting region of the windshield. A first electrode portion and a second electrode portion are arranged to face each other in a vertical direction of a vehicle. A third electrode portion and a fourth electrode portion are arranged to face each other in a direction crossing the vertical direction of the vehicle. A control device is capable of implementing multiple energization modes. In a first mode among the plurality of energization modes, one of the first electrode portion and the second electrode portion is set to a high potential and the other is set to a low potential, or one of the third electrode portion and the fourth electrode portion is set to a high potential and the other is set to a low potential.

Abstract: In a wireless network including a wireless LAN device having a base station function compatible with the IEEE 802.11e standard and a wireless LAN device having a terminal function compatible with the standard, a band-guaranteed data reception check timer 104? starts measuring a preset time when the terminal receives band-guaranteed data from the base station after a band acquisition response signal is transmitted from the base station to the terminal and a band-guaranteed data transfer is established between the base station and the terminal. If band-guaranteed data is not received from the base station before the measurement of the preset time is completed, the terminal determines that the wireless network connection has been disconnected to request the base station for re-connection of the wireless network after passage of the preset time.

Abstract: When the communication channel is to be changed, a more optimal communication channel is determined by summing up the results of measuring communication states transmitted from individual wireless terminals A, B, and C and making a collective judgment. Weighting coefficients are set to the individual wireless terminals A, B, and C. Values indicating whether or not the respective communication states of the individual wireless terminals are optimal with channels ch1 to ch4 to be used for communication (which are, e.g., 1, 0, 1, 2 with the respective channels ch1, ch2, ch3, and ch4 for the wireless terminal A and larger as the communication states are less optimal) are multiplied by the weight coefficient (the value of 3). The resulting values are summed up on a per-channel basis and the most optimal communication channel (of which the summed value is lowest) is selected. As a result, wave interference with the other wireless terminal is reduced.

Abstract: In measurement of wireless channels in an IEEE 802.11 wireless local area network (WLAN), in the case of multi-channel measurement as in North America in which eight wireless channels Ch1 through Ch8 are available, channel measurement according to a predetermined algorithm is made in which odd-numbered channels Ch1, Ch3, Ch5 and Ch7 are first measured, and if radio interference occurs in channel Ch5, channels Ch4 and Ch6 adjacent to channel Ch5 are measured. This shortens the measurement time that conventionally corresponds to measurement of the eight channels to the time of six channels, i.e., the sum of the measurement time for the odd-numbered channels and that for the channels adjacent to the interference-occurring channel.

Abstract: A method for determining a measurement time period for measuring a propagation environment in a wireless station set having a plurality of wireless stations, between which wireless communication is made using a channel selected from a plurality of channels different in frequency. The method includes the steps of: obtaining a measurement time period in another wireless station set having a plurality of wireless stations; and determining the measurement time period in the own wireless station set so as to have a time period that does not overlap the obtained measurement time period.

Abstract: In a wireless network including a wireless LAN device having a base station function compatible with the IEEE 802.11e standard and a wireless LAN device having a terminal function compatible with the standard, a band-guaranteed data reception check timer 104? starts measuring a preset time when the terminal receives band-guaranteed data from the base station after a band acquisition response signal is transmitted from the base station to the terminal and a band-guaranteed data transfer is established between the base station and the terminal. If band-guaranteed data is not received from the base station before the measurement of the preset time is completed, the terminal determines that the wireless network connection has been disconnected to request the base station for re-connection of the wireless network after passage of the preset time.

Abstract: In a wireless network structure which includes a wireless LAN device having a base station function (host device) which is compliant with IEEE802.11h and at least one wireless LAN device having a terminal function (slave device) which is not compliant with IEEE802.11h, the incompliant terminal transmits a probe request to the base station for confirming the presence of the base station. When the base station has dynamically switched its channel (frequency), a probe response is not returned from the base station to the terminal. Thus, the incompliant terminal transmits a probe request through a different channel in order to confirm the presence of the base station. The incompliant terminal repeats the above channel search process till the base station is found.

Abstract: In a wireless network structure which includes a wireless LAN device having a base station function (host device) which is compliant with IEEE802.11h and at least one wireless LAN device having a terminal function (slave device) which is not compliant with IEEE802.11h, the incompliant terminal transmits a probe request to the base station for confirming the presence of the base station. When the base station has dynamically switched its channel (frequency), a probe response is not returned from the base station to the terminal. Thus, the incompliant terminal transmits a probe request through a different channel in order to confirm the presence of the base station. The incompliant terminal repeats the above channel search process till the base station is found.

Abstract: A wireless communication system, a wireless terminal and a wireless communication method which can realize a high throughput even when communication is performed between plural terminal pairs are provided. A wireless communication system according to the present invention includes a wireless LAN base station and plural terminals which mutually communicate through the wireless LAN base station, each of the terminals includes a communication unit operable to perform inter-terminal direct communication with an other terminal, using a second wireless channel that is different from a first wireless channel, the first wireless channel being used in wireless communication with the base station, the inter-terminal direct communication being communication that bypasses the wireless LAN base station.

Abstract: A method for determining a measurement time period for measuring a propagation environment in a wireless station set having a plurality of wireless stations, between which wireless communication is made using a channel selected from a plurality of channels different in frequency. The method includes the steps of: obtaining a measurement time period in another wireless station set having a plurality of wireless stations; and determining the measurement time period in the own wireless station set so as to have a time period that does not overlap the obtained measurement time period.

Abstract: When the communication channel is to be changed, a more optimal communication channel is determined by summing up the results of measuring communication states transmitted from individual wireless terminals A, B, and C and making a collective judgment. Weighting coefficients are set to the individual wireless terminals A, B, and C. Values indicating whether or not the respective communication states of the individual wireless terminals are optimal with channels ch1 to ch4 to be used for communication (which are, e.g., 1, 0, 1, 2 with the respective channels ch1, ch2, ch3, and ch4 for the wireless terminal A and larger as the communication states are less optimal) are multiplied by the weight coefficient (the value of 3). The resulting values are summed up on a per-channel basis and the most optimal communication channel (of which the summed value is lowest) is selected. As a result, wave interference with the other wireless terminal is reduced.

Abstract: In measurement of wireless channels in an IEEE 802.11 wireless local area network (WLAN), in the case of multi-channel measurement as in North America in which eight wireless channels Ch1 through Ch8 are available, channel measurement according to a predetermined algorithm is made in which odd-numbered channels Ch1, Ch3, Ch5 and Ch7 are first measured, and if radio interference occurs in channel Ch5, channels Ch4 and Ch6 adjacent to channel Ch5 are measured. This shortens the measurement time that conventionally corresponds to measurement of the eight channels to the time of six channels, i.e., the sum of the measurement time for the odd-numbered channels and that for the channels adjacent to the interference-occurring channel.

Abstract: The objective of the invention is the constant optimization of the sizes of buffers required for a transmission process and a reception process, and the effective use of memory resources. A contents processor includes a contents change detector. When the contents are changed, the contents change detector transmits to a wireless communication unit a contents identifier corresponding to contents that are to be newly processed by the wireless communication unit. The wireless communication unit includes a contents information table in which information concerning the contents is stored. The wireless communication unit examines the contents information table, obtains the sizes of buffers required for a transmission process and a reception process, based on the contents identifier transmitted by the contents processor, and redistributes the transmission buffer and the reception buffer for a buffer queue.