Ofdm Transmitting Apparatus, Ofdm Receiving Apparatus, and Their Methods
An OFDM transmitting apparatus capable of preventing any degradation of the throughput of the communication system without assigning any resources of the communication system for transmission of a control channel. In the apparatus, a switch ( 121 ) selectively supplies, based on the encoded data of the control channel outputted from an encoding part ( 110 ), a plurality of outputs from a repetition part ( 103 ) to pattern generating parts ( 122 - 1 to 122 - 2 ). In this way, a plurality of types of repetition patterns can be used to generate outbound data. An assigning part ( 123 ) maps the outbound data generated by one of the pattern generating parts to a subcarrier.
1 . An OFDM transmitting apparatus comprising:
a determining section that determines a repetition pattern for first information according to content of second information; and
a transmitting section that performs repetition of the first information in the repetition pattern and transmits a result.
2 . An OFDM transmitting apparatus comprising:
a replicating section that replicates a data symbol of a data channel into a plurality of data symbols and generates a repetition symbol;
a determining section that determines a repetition pattern of the repetition symbol, said pattern being an arrangement in a two-dimensional plane composed of a time axis and a frequency axis, according to content of control information of the data channel; and
an assigning section that assigns the repetition symbol to a transmitting subcarrier based on the repetition pattern.
3 . The OFDM transmitting apparatus according to claim 2 , further comprising a coding section that performs error correction coding on the data channel.
4 . The OFDM transmitting apparatus according to claim 2 , further comprising an adding section that adds a CRC (Cyclic Redundancy Check) code to a group of a plurality of repetition symbols arranged in a same repetition pattern in the determining section.
5 . An OFDM receiving apparatus comprising:
a determining section that determines a repetition pattern used for a received signal, using a plurality of predetermined repetition patterns, and extracts control information of the received signal based on a determination result; and
a combining section that combines a data channel signal from the received signal, using determined repetition pattern.
6 . The OFDM receiving apparatus according to claim 5 , wherein the determining section comprises:
a comparing section that compares the received signal to each of the plurality of predetermined repetition patterns;
a calculating section that calculates a soft decision value corresponding to the control information, from a comparison result in the comparing section; and
a decoding section that performs soft decision error correction decoding on the control information using the soft decision value.
7 . An OFDM receiving apparatus comprising:
a combining section that combines a plurality of data channel signals from received signals, using a plurality of predetermined repetition patterns;
a determining section that determines a repetition pattern used for a received signal, using the plurality of data channel signals, and extracts control information of the received signal based on a determination result; and
a selecting section that selects a data channel signal corresponding to a determined repetition pattern, from the plurality of data channel signals.
8 . The OFDM receiving apparatus according to claim 7 , wherein:
the determining section comprises:
a decoding section that performs error correction decoding on the plurality of data channel signals and obtains a plurality of decoded signals; and
a CRC determining section that performs CRC determination on the plurality of decoded signals, and extracts the control information based on this CRC determination result; and
the selecting section selects one from the plurality of decoded signals according to the CRC determination result.
9 . The OFDM receiving apparatus according to claim 7 , wherein:
the determining section comprises:
a first decoding section that performs error correction decoding on the plurality of data channel signals and obtains a plurality of decoded signals;
a calculating section that calculating a soft decision value corresponding to the control information, from the plurality of decoded signals; and
a second decoding section that performs soft decision error correction decoding on the control information using the soft decision value, and obtains decoded signals of the control information; and
the selecting section selects one from the plurality of decoded signals obtained by the first decoding section, based on the decoded signals obtained by the second decoding section.
10 . A communication terminal apparatus comprising the OFDM transmitting apparatus of claim 1 .
11 . A base station apparatus comprising the OFDM transmitting apparatus of claim 1 .
12 . A communication terminal apparatus comprising the OFDM receiving apparatus of claim 5 .
13 . A base station apparatus comprising the OFDM receiving apparatus of claim 5 .
14 . A communication terminal apparatus comprising the OFDM receiving apparatus of claim 7 .
15 . A base station apparatus comprising the OFDM receiving apparatus of claim 7 .
16 . An OFDM transmission method comprising the steps of:
determining a repetition pattern of a data channel according to content of control information of the data channel; and
performing repetition of the data channel in the repetition pattern and transmitting a result.
17 . An OFDM receiving method comprising the steps of:
determining a repetition pattern used in received signal, using a plurality of predetermined repetition patterns;
extracting control information of the received signal, based on a determination result; and
combining a data channel signal from the received signal, using the determined repetition pattern.
18 . An OFDM receiving method comprising the steps of:
combining a plurality of data channel signals from received signals, using a plurality of predetermined repetition patterns;
determining a repetition pattern used in a received signal, using the plurality of data channel signals;
extracting control information of the received signal, based on the determination result; and
selecting a data channel signal corresponding to a determined repetition pattern, from the plurality of data channel signals.