Radio apparatus

摘要

A radio apparatus includes a first receiver that is a processing unit for amplifying and frequency converting a radio signal received via an antenna, thereby outputting an IF signal; a detector unit for detecting a preamble signal from the IF signal; a second receiver for amplifying and quadrature demodulating the radio signal, thereby generating an I-signal and a Q-signal; a demodulator unit for demodulating the I-signal and Q-signal to generate a data signal; and a control unit for halting the operation of the first receiver and further activating the second receiver when the detector unit detects the preamble signal and for activating the first receiver and halting the operation of the second receiver when the demodulator unit completes the demodulation of the I-signal and Q-signal.

主权项

1. A radio apparatus comprising:
a first receiver comprising:
a first amplifier that generates a first amplified signal by amplifying a first radio signal received by an antenna;a first mixer that generates an IF signal by converting a frequency of the first amplified signal; anda first filter that suppresses a portion of the IF signal which is outside of a desired band; a detector that detects a preamble from the IF signal which is outputted from the first receiver; a second receiver comprising:
a second amplifier that generates a second amplified signal by amplifying a second radio signal received by the antenna, wherein a frequency of the second radio signal is the same as a frequency of the first radio signal;a second mixer that generates an I signal by converting a frequency of the second amplified signal;a second filter that suppresses a portion of the I signal which is outside of a desired band;a third mixer that generates a Q signal by converting the frequency of the second amplified signal; anda third filter that suppresses a portion of the Q signal which is outside of a desired band; a demodulator that demodulates the I signal and the Q signal each of which is outputted from the second receiver; and a controller that halts the operation of the first receiver and activates the second receiver when the detector detects the preamble, and activates the first receiver and halts the operation of the second receiver during standby time; wherein the first filter has a first capacitor and a first resistance, to filter the IF signal; and wherein each of the second filter and the third filter includes (i) a second capacitor having a value larger than the first capacitor, and (ii) a second resistance having a resistance value smaller than the first resistance, to filter the I signal and the Q signal, respectively.