Patent ID: 8199854

Claim:
A mobile communication system comprising: a transmitter that performs transmission of data at a transmission rate of 2400×(n+1) (n: natural number) [bps]; and a receiver that receives data transmitted from the transmitter, the transmitter includes: encoding means for encoding predetermined data to generate a binary signal; symbol converting means for sequentially converting the binary signal generated by the encoding means into a 2 (n+1) -ary symbol, which includes (2 (n+1) +1−2 k) (1≦k≦2 (n+1) ) values, (n+1) bits at a time and outputting the symbol; a first base band filter that blocks an unnecessary frequency component of the symbol inputted from the symbol converting means and outputs a waveform signal; and frequency shifting and modulating (FM) means for transmitting a signal, which is obtained by shifting to modulate a frequency according to a magnitude of an amplitude of the waveform signal inputted from the first base band filter, to the receiver, the receiver includes: demodulating means for demodulating the signal transmitted from the transmitter and received and outputting a 2 (n+1) -ary signal; a second base band filter that blocks an unnecessary frequency component of the 2 (n+1) -ary signal outputted from the demodulating means and outputs the 2 (n+1) -ary signal; binary signal converting means for sequentially converting the 2 (n+1) -ary signal inputted from the second base band filter into the binary signal of (n+1) bits and outputting the binary signal; and decoding means for decoding the binary signal inputted from the binary signal converting means and outputting the predetermined data, and wherein when a symbol of +(2 (n+1) −1) and a symbol of −(2 (n+1) −1) are alternately and repeatedly outputted from the symbol converting means, a frequency shift of the signal outputted from the frequency shifting and modulating means is set within a range of ±0.822 [kHz] to ±0.952 [kHz], and wherein the transmission path from the encoding means included in the transmitter to the decoding means included in the receiver forms a Nyquist transmission path.