| 摘要 |
In a wireless communication apparatus which has the functions of both ASK modulation and QPSK modulation, which can be manufactured at a low cost, and which is small in size, an output terminal (5Q) of a QPSK modulator (5) is connected to a carrier wave input terminal (1A9 of an ASK modulator (1) via a switch (15). Also, an antenna (4) is connected to an output terminal (1C) of the ASK modulator (1) via a switch (16). Furthermore, a mixer (13) is provided between the switches (15) and (16). The switch (15) connects the QPSK modulator (5) and the ASK modulator (1) at the time of a transmission, whereas it connects the QPSK modulator (5) and the mixer (13) at the time of a reception. The switch (16) connects the ASK modulator (1) and the antenna (4) at the time of a transmission, whereas it connects the antenna (4) and the mixer (13) at the time of a reception. Thus, at the time of a transmission, an ASK-modulated wave or a QPSK-modulated wave is output using the ASK modulator (1) and the QPSK modulator (5). At the time of a reception, a sine wave is output by the QPSK modulator (5) and a data signal is down-converted, detected, or demodulated by the mixer (13). |
