Communication apparatus and reception method
View Patent ↗It is possible to provide a radio communication terminal device and a radio transmission method which can improve reception performance of a CQI and a reference signal. A phase table storage unit stores a phase table which correlates the amount of cyclic shift to complex coefficients {w1, W2} to be multiplied on the reference signal. A complex coefficient multiplication unit reads out a complex coefficient corresponding to the amount of cyclic shift indicated by resource allocation information, from the phase table storage unit and multiplies the read-out complex coefficient on the reference signal so as to change the phase relationship between the reference signals in a slot.
1. A communication apparatus comprising:
a reference signal generator configured to generate a reference signal using an index related to a cyclic shift and a pair of coefficients in accordance with a switching signal, wherein the switching signal switches between a first correspondence relationship and a second correspondence relationship, each defining a relationship between the index related to a cyclic shift and the pair of coefficients, the first correspondence relationship defines a first pair of coefficients corresponding to an even number index related to a cyclic shift and a second pair of coefficients corresponding to an odd number index related to a cyclic shift and the second correspondence relationship defines the first pair of coefficients corresponding to the odd number index related to a cyclic shift and the second pair of coefficients corresponding to the even number index related to a cyclic shift; and
a transmitter configured to transmit the generated reference signal.
2. The communication apparatus according to claim 1 , wherein the first pair of coefficients is [1 1], and the second pair of coefficients is [1 −1].
3. The communication apparatus according to claim 1 , wherein
the reference signal generator generates the reference signal by determining a pair of complex coefficients according to a table showing a relationship between indexes related to the cyclic shift and pairs of coefficients and by multiplying a signal sequence by the determined pair of complex coefficients.
4. A transmission method comprising:
generating a reference signal using an index related to a cyclic shift and a pair of coefficients in accordance with a switching signal, wherein the switching signal switches between a first correspondence relationship and a second correspondence relationship, each defining a relationship between the index related to a cyclic shift and the pair of coefficients, the first correspondence relationship defines a first pair of coefficients corresponding to an even number index related to a cyclic shift and a second pair of coefficients corresponding to an odd number index related to a cyclic shift and the second correspondence relationship defines the first pair of coefficients corresponding to the odd number index related to a cyclic shift and the second pair of coefficients corresponding to the even number index related to a cyclic shift; and
transmitting the generated reference signal.
5. The method according to claim 4 , wherein the first pair of coefficients is [1 1], and the second pair of coefficients is [1 −1].
6. The method according to claim 4 , wherein
the reference signal is generated by determining a pair of complex coefficients according to a table showing a relationship between indexes related to the cyclic shift and pairs of coefficients and by multiplying a signal sequence by the determined pair of complex coefficients.