Radio transmitting apparatus, radio receiving apparatus, and M-ary modulation communication system
View Patent ↗P/S conversion section 302 performs parallel/serial conversion of data sequences # 1 through # 4 input in parallel, in accordance with control by assignment control section 303 , so that data to a higher-priority communication terminal is assigned to an upper bit in one symbol; M-ary modulation section 304 performs M-ary modulation on the data that has been subject to parallel/serial conversion; S/P conversion section 305 converts a symbol that has been subject to M-ary modulation to parallel form; multipliers 306 - 1 through 306 - 4 execute spreading processing on the symbols output in parallel; multiplexing section 309 multiplexes the symbol that has been subject to spreading processing with an assignment notification signal that has been subject to spreading processing; and radio transmitting section 310 transmits the multiplex signal.
1. A data transmission method comprising the steps of:
transmitting a 16QAM symbol based on a string of four bits to a data reception apparatus in a first transmission;
receiving a retransmission request from said data reception apparatus;
swapping bit positions of said string of four bits within another 16QAM symbol to produce an arranged string of four bits; and
transmitting the other 16QAM symbol based on said arranged string of four bits to said data reception apparatus in a retransmission, wherein:
said swapping step swaps a bit position of a first bit of said string of four bits for a bit position of a fourth bit of said string of four bits, and swaps a bit position of a second bit of said string of four bits for a bit position of a third bit of said string of four bits.
2. A data reception method comprising the steps of:
receiving a 16QAM symbol based on a string of four bits from a data transmission apparatus in a first transmission;
performing error detection with respect to said string of four bits;
transmitting a retransmission request to said data transmission apparatus if an error is detected;
receiving another 16QAM symbol based on an arranged string of four bits from said data transmission apparatus in a retransmission; and
swapping bit positions of said arranged string of four bits within the other 16QAM symbol to produce a rearranged string of four bits, wherein:
said arranged string of four bits is produced by swapping a bit position of a first bit of said string of four bits for a bit position of a fourth bit of said string of four bits, and swapping a bit position of a second bit of said string of four bits for a bit position of a third bit of said string of four bits.
3. A data transmission apparatus comprising:
a transmitting section that transmits a 16QAM symbol based on a string of four bits to a data reception apparatus in a first transmission;
a receiving section that receives a retransmission request from said data reception apparatus; and
a swapping section that swaps bit positions of said string of four bits within another 16QAM symbol to produce an arranged string of four bits, wherein:
said transmitting section transmits the other 16QAM symbol based on said arranged string of four bits to said data reception apparatus in a retransmission, and
said swapping section swaps a bit position of a first bit of said string of four bits for a bit position of a fourth bit of said string of four bits, and swaps a bit position of a second bit of said string of four bits for a bit position of a third bit of said string of four bits.
4. A data reception apparatus comprising:
a receiving section that receives a 16QAM symbol based on a string of bits from a data transmission apparatus in a first transmission, and receives another 16QAM symbol based on an arranged string of bits from said data transmission apparatus in a retransmission;
an error detection section that performs error detection with respect to said string of four bits;
a transmitting section that transmits a retransmission request to said data transmission apparatus if an error is detected; and
a swapping section that swaps bit positions of said arranged string of four bits within the other 16QAM symbol to produce a rearranged string of four bits, wherein:
said swapping section swaps a bit position of a first bit of said arranged string of four bits for a bit position of a fourth bit of said arranged string of four bits, and swaps a bit position of a second bit of said arranged string of four bits for a bit position of a third bit of said arranged string of four bits.
5. A data communication method comprising the steps of:
transmitting, at a data transmission apparatus, a 16QAM symbol based on a string of four bits to a data reception apparatus in a first transmission;
receiving, at said data reception apparatus, said 16QAM symbol from said data transmission apparatus;
performing, at said data reception apparatus, error detection with respect to said string of four bits;
transmitting, at said data reception apparatus, a retransmission request to said data transmission apparatus if an error is detected;
receiving, at said data transmission apparatus, said retransmission request from said data reception apparatus;
swapping, at said data transmission apparatus, bit positions of said string of four bits within another 16QAM symbol to produce an arranged string of four bits;
transmitting, at said data transmission apparatus, the other 16QAM symbol based on said arranged string of four bits to said data reception apparatus in a retransmission; and
receiving, at said data reception apparatus, said other 16QAM symbol based on said arranged string of four bits from said data transmission apparatus, wherein:
said swapping step swaps a bit position of a first bit of said string of four bits for a bit position of a fourth bit of said string of four bits, and swaps a bit position of a second bit of said string of four bits for a bit position of a third bit of said string of four bits.
6. A data communication system comprising a data transmission apparatus and a data reception apparatus;
said data transmission apparatus comprising:
a transmitting section that transmits a 16QAM symbol based on a string of four bits to said data reception apparatus in a first transmission;
a receiving section that receives a retransmission request from said data reception apparatus; and
a swapping section that swaps bit positions of said string of four bits within another 16QAM symbol to produce an arranged string of four bits, wherein:
said transmitting section transmits the other 16QAM symbol based on said arranged string of four bits to said data reception apparatus in a retransmission; and
said swapping section swaps a bit position of a first bit of said string of four bits for a bit position of a fourth bit of said string of four bits, and swaps a bit position of a second bit of said string of four bits for a bit position of a third bit of said string of four bits; and
said data reception apparatus comprising:
a receiving section that receives said 16QAM symbol based on said string of four bits from said data transmission apparatus in said first transmission;
an error detection section that performs error detection with respect to said string of four bits; and
a transmitting section that transmits said retransmission request to said data transmission apparatus if an error is detected, wherein:
said receiving section receives said arranged string of bits from said data transmission apparatus in said retransmission.