Communication apparatus and method

1. A communication method for a code division multiple access (CDMA) communication system transmitting a transport channel composite including data of a plurality of transport channels between a base station and a communication terminal via a physical channel, said physical channel having a maximum physical rate and rate matching is performed on data of each of said transport channels to change a transmission rate, the method comprising:

a first step of calculating a ratio of said maximum physical rate to a maximum value of estimated transport channel composite rates;

a second step of calculating a rate matching ratio for each of said transport channels by multiplying the ratio obtained in said first step by a rate matching parameter for said transport channel, said rate matching parameter controlling said rate matching ratio for said transport channel;

a third step of calculating a number of bits of each of said transport channels after said rate matching by multiplying said rate matching ratio by a number of bits before said rate matching per radio frame of each of said transport channels and multiplying a result of the multiplication by a number of radio frames per transmission time interval of the relevant transport channel;

a fourth step of calculating a variation between the number of bits of each of said transport channels after said rate matching obtained in said third step and the number of bits of the relevant transport channel before the rate matching; and

a fifth step of correcting said variation using an intermediate variation for at least one of said transport channels, in the case that a total sum of the number of bits per radio frame after said rate matching for said plurality of transport channels exceeds said maximum physical rate, said intermediate variation being calculated based on said rate matching parameter and the number of bits per radio frame before said rate matching for at least one of said transport channels.

2. A communication apparatus used in a code division multiple access (CDMA) communication system transmitting a transport channel composite including data of a plurality of transport channels via a physical channel, said physical channel having a maximum physical rate, and said communication apparatus having rate matching means for performing rate matching on data of each of said transport channels to change a transmission rate by repeating or puncturing some bits of the data of each of said transport channels, said communication apparatus comprising:

first means for calculating a ratio of said maximum physical rate to a maximum value of estimated transport channel composite rates;

second means for calculating a rate matching ratio for each of said transport channels by multiplying said ratio obtained by said first means by a rate matching parameter for said transport channel, said rate matching parameter controlling said rate matching ratio for said transport channel;

third means for calculating a number of bits of each of said transport channels after said rate matching by multiplying said rate matching ratio by a number of bits before said rate matching per radio frame of each of said transport channels and multiplying a result of the multiplication by a number of radio frames per transmission time interval of the relevant transport channel;

fourth means for calculating a variation between a number of bits of each of said transport channels after said rate matching obtained by said third means and a number of bits of the relevant transport channel before said rate matching; and

fifth means for correcting said variation using an intermediate variation for at least one of said transport channels, in the case that a total sum of the number of bits per radio frame after said rate matching for said plurality of transport channels exceeds said maximum physical rate, said intermediate variation being calculated based on said rate matching parameter and the number of bits per radio frame before said rate matching for at least one of said transport channels.

3. A communication method of a communication apparatus transmitting a transport channel composite including data of a plurality of transport channels via a physical channel, said physical channel having a maximum physical rate, performing rate matching process on data of each of said transport channels to change a transmission rate, and calculating a variation between a number of bits of each of said transport channels after the rate matching process and a number of bits of each of said transport channels before the rate matching process, the variation being used to perform rate matching process, the method comprising:

a first step of calculating a ratio of said maximum physical rate to a maximum value of estimated transport channel composite rates;

a second step of calculating a rate matching ratio for each of said transport channels by multiplying said ratio obtained in said first step by rate matching parameter for said transport channel, said rate matching parameter controlling said rate matching ratio for said transport channel;

a third step of calculating a variation between the number of bits after said rate matching and the number of bits before said rate matching for each of said transport channels, the number of bits after said rate matching being calculated by multiplying said rate matching ration by the numbers of bits before said rate matching; and

a fourth step of correcting said variation using an intermediate variation for at least one of said transport channels, in the case that a total sum of the number of bits per radio frame after said rate matching for said plurality of transport channels exceeds said maximum physical rate, said intermediate variation being calculated based on said rate matching parameter and the number of bits per radio frame before said rate matching for at least one of said transport channels.

4. The communication method according to claim 3 , wherein said estimated transport channel composite rates are calculated using said rate matching parameter.

5. The communication method according to claim 3 , further comprising:

receiving step of receiving data of which the transmission rate is changed by the rate matching process via said physical channel;

processing step of performing process of changing a transmission rate on data received in the receiving step, based on said variation corrected in the fourth step.

6. The communication method according to claim 3 , wherein

the processing step performs the reverse of the rate matching process performed in a base station, based on said variation corrected in the fourth step.

7. A communication apparatus transmitting a transport channel composite including data of a plurality of transport channels via a physical channel, said physical channel having a maximum physical rate, performing rate matching on data of each of said transport channels to change a transmission rate, and calculating a variation between a number of bits of each of said transport channels after the rate matching and a number of bits of each of said transport channels before the rate matching, the variation being used to perform rate matching, the communication apparatus comprising:

first means for calculating a ratio of said maximum physical rate to a maximum value of estimated transport channel composite rates;

second means for calculating a rate matching ratio for each of said transport channels by multiplying said ratio obtained in said first means by rate matching parameter for said transport channel, said rate matching parameter controlling said rate matching ratio for said transport channel;

third means for calculating a variation between the number of bits after the rate matching and the number of bits before the rate matching for each of said transport channels, the number of bits after said rate matching being calculated by multiplying said rate matching ratio by the numbers of bits before said rate matching; and

fourth means for correcting said variation using an intermediate variation for at least one of said transport channels, in the case that a total sum of the number of bits per radio frame after said rate matching for said plurality of transport channels exceeds said maximum physical rate, said intermediate variation being calculated based on said rate matching parameter and the number of bits per radio frame before said rate matching for at least one of said transport channels.

8. The communication apparatus according to claim 7 , wherein said estimated transport channel composite rates are calculated using said rate matching parameter.

9. The communication apparatus according to claim 7 , further comprising:

receiving means for receiving data of which the transmission rate is changed by the rate matching process via said physical channel; and

processing means for performing process of changing a transmission rate on data received by the receiving means, based on said variation corrected in the fourth means for correcting.

10. The communication apparatus according to claim 7 , wherein

the processing means performs the reverse of the rate matching process performed in a base station, based on said variation corrected by the fourth means.