Patent ID: 7496146

Claim:
A base station for receiving an up-link signal from a telephone and transmitting a first down-link signal and a second down-link signal to the telephone as a down-link signal, comprising: when the up-link signal is transmitted from the telephone to the base station: a receiver operable to receive the up-link signal, wherein the up-link signal has information of a data stream, the data stream is modulated according to a QPSK; and demodulator operable to demodulate the up-link signal to produce the data stream; when the down-link signal is transmitted from the base station to the telephone: a first error correction code (ECC) encoder to operable to ECC encode a first data stream to produce an ECC encoded first data stream; a second error correction code (ECC) encoder to operable to ECC encode a second data stream to produce an ECC encoded second data stream; wherein a scheme of the first ECC encoder is different from a scheme of the second ECC encoder, and wherein an error correction power of the second error correction code for the ECC encoded data stream is changeable; a modulator operable to modulate the ECC encoded first data stream according to a QPSK to produce a first modulated signal and modulate the ECC encoded second data stream according to an n-level PSK or an n-level QAM to produce a second modulated signal, wherein the first data stream includes information representing the value of n; and a transmitter operable to transmit the first modulated signal as the first down-link signal and transmit the second modulated signal as the second down-link signal.