RADIO COMMUNICATION APPARATUS CAPABLE OF SWITCHING MODULATION SCHEMES
A radio communication apparatus includes a QPSK modulator that modulates transmission data to produce a QPSK modulation signal and a 64QAM modulator that modulates transmission data to produce a 64QAM modulation signal. A radio transmitter receives the QPSK modulation signal and the 64QAM modulation signal and outputs a transmission signal. An average transmission power of the QPSK modulation signal and the 64QAM modulation signal are within a predetermined output power range.
1 . A radio communication apparatus, comprising:
a QPSK modulator to modulate transmission data to produce a QPSK modulation signal;
a 64QAM modulator to modulate transmission data to produce a 64QAM modulation signal; and
a radio transmitter to receive the QPSK modulation signal and the 64QAM modulation signal and output a transmission signal,
wherein an average transmission power of the QPSK modulation signal and the 64QAM modulation signal are within a predetermined output power range.
2 . The radio communication apparatus according to claim 1 , further comprising a receiver to receive information regarding a radio wave propagation environment transmitted by a communication party, wherein the QPSK modulator, the 64QAM modulator, and the average transmission powers are controlled based upon the received information.
3 . The radio communication apparatus according to claim 2 , wherein the received information includes information regarding communications traffic.
4 . The radio communication apparatus according to claim 2 , wherein the QPSK modulator is selectable using a control signal and the 64QAM modulator is selectable using a control signal.
5 . The radio communication apparatus according to claim 1 , wherein the radio communication apparatus is configured to use orthogonal frequency division multiplexing (OFDM).
6 . The radio communication apparatus according to claim 5 , wherein the transmission data includes a frame having one or more preambles, one or more pilots, and data.
7 . The radio communication apparatus according to claim 6 , wherein the frame is an OFDM signal frame and a pilot is inserted in the OFDM signal frame.
8 . The radio communication apparatus according to claim 1 , wherein a magnitude of a modulated pilot is greater than a magnitude of modulated data.
9 . The radio communication apparatus according to claim 1 , wherein a maximum transmission output power of the QPSK modulation signal and the 64QAM modulation signal are the same.
10 . A radio communication method, comprising:
a QPSK modulator modulating transmission data to produce a QPSK modulation signal;
a 64QAM modulator modulating transmission data to produce a 64QAM modulation signal; and
a radio transmitter receiving the QPSK modulation signal and the 64QAM modulation signal and outputing a transmission signal,
wherein an average transmission power of the QPSK modulation signal and the 64QAM modulation signal are within a predetermined output power range.
11 . The radio communication method according to claim 10 , further comprising:
receiving information regarding a radio wave propagation environment transmitted by a communication party,
wherein the QPSK modulator, the 64QAM modulator, and the average transmission powers are controlled based upon the received information.
12 . The radio communication method according to claim 11 , wherein the received information includes information regarding communications traffic.
13 . The radio communication method according to claim 11 , further comprising:
selecting the QPSK modulator using a control signal, and
selecting the 64QAM modulator using a control signal.
14 . The radio communication method according to claim 10 , further comprising:
generating orthogonal frequency division multiplexing (OFDM) signal based on the QPSK modulation signal and the 64QAM modulation signal.
15 . The radio communication method according to claim 14 , wherein the transmission data includes a frame having one or more preambles, one or more pilots, and data.
16 . The radio communication method according to claim 15 , wherein the frame is an OFDM signal frame and a pilot is inserted in the OFDM signal frame.
17 . The radio communication method according to claim 10 , wherein a magnitude of a modulated pilot is greater than a magnitude of modulated data.
18 . The radio communication method according to claim 10 , wherein a maximum transmission output power of the QPSK modulation signal and the 64QAM modulation signal are the same.