Abstract: A data transmission apparatus transmits data signals “S1” and “S2” containing identical serial data “ds” in two frequency bands, and a data reception apparatus receives those data signals “S1” and “S2.” Parallel data “dpl” and “dpl2” obtained from the data signals “S1” and “S2” is subjected to selection or synthesis in a subcarrier selection/demodulation circuit so as to be demodulated into serial data “dsx,” which is then outputted to a MAC section.

Abstract: In a display device, when an application operating section is to communicate, each communication state detecting section detects a communication state of each radio communication section. A physical layer selecting section then determines if each physical layer is capable of providing an effective throughput required by each application operating section by each radio communications section. Furthermore, the physical layer selecting section selects from the physical layers a physical layer available for communications of each application operating section.

Abstract: A data transmission apparatus transmits data signals “S1” and “S2” containing identical serial data “ds” in two frequency bands, and a data reception apparatus receives those data signals “S1” and “S2.” Parallel data “dpl” and “dpl2” obtained from the data signals “S1” and “S2” is subjected to selection or synthesis in a subcarrier selection/demodulation circuit so as to be demodulated into serial data “dsx,” which is then outputted to a MAC section.

Abstract: A wireless transmission/reception card has a pole-shaped antenna for wireless transmission and reception, and the length direction of the antenna is substantially parallel to the main faces of the card. A headset has a slot in which the wireless transmission/reception card is inserted, and, when the card is inserted in the slot, the pole-shaped antenna of the card is set upright substantially in the vertical direction in the normal use state of the headset. The wireless transmission/reception card excels in portability, and, when inserted in the slot of the headset, helps enhance the antenna gain in the horizontal plane in the normal use state.