Transmitter and receiver devices performing repetition before interleaving and puncturing after interleaving and methods thereof

1. A transmitter device for a wireless communication system, the transmitter device comprising:

a transceiver that receives at least one stream of information bits;

a memory comprising instructions; and

a processor coupled to the transceiver and the memory, wherein the instructions cause the processor to:

encode the at least one stream of information bits using at least one error correction code to obtain at least one mother code word having a mother code rate (R M );

perform interleaving and rate matching based on the R M and a transmission code rate (R TX ) associated with the at least one mother code word, wherein the R M comprises a ratio of a number of information bits divided by a number of coded bits, wherein the R TX comprises a ratio of the number of information bits divided by a total number of bits transmitted over resource elements used for data transmission, and wherein performing interleaving and rate matching based on the R M and the R TX comprises:

first interleaving the at least one mother code word to obtain an interleaved code word, and second rate matching the interleaved code word to obtain a shortened code word having a code rate that is higher than the R M when the R M is smaller than the R Tx associated with the at least one mother code word; and

first rate matching the at least one mother code word to obtain an extended code word, and second interleaving the extended code word having a code rate that is lower than the R M when the R M is not smaller than the R Tx associated with the at least one mother code word; and

modulate the shortened or extended code word to obtain modulated symbols, and

wherein the transceiver transmits a signal comprising the modulated symbols over a radio channel of the wireless communication system.

2. The transmitter device according to claim 1 , wherein the processor comprises a Low Density Spreading (LDS) matrix interleaver for interleaving the at least one mother code word or extended code word.

3. The transmitter device according to claim 2 , wherein the LDS matrix interleaver applies column permutation on elements of interleaver matrices.

4. The transmitter device according to claim 2 , wherein the LDS matrix interleaver size is adapted to different code rates associated with different streams of information bits for transmission.

5. The transmitter device according to claim 2 , wherein the LDS matrix interleaver adds dummy bits to the shortened or extended code word such that a code word length of the shortened or extended code word is a multiple of the number of columns of an interleaver matrix.

6. The transmitter device according to claim 2 , wherein the LDS matrix interleaver is a rectangular interleaver.

7. The transmitter device according to claim 1 , wherein the transmitter device comprises a Code Division Multiple Access (CDMA) transmitter, a High Speed Downlink Packet Access (HSDPA) transmitter, or a Multi Carrier (MC)-CDMA transmitter adapted for transmitting the signal.

8. The transmitter device according to claim 7 , wherein the CDMA transmitter, the HSDPA transmitter, or the MC-CDMA transmitter is configured to use more signature sequences than chips for transmission when transmitting the signal.

9. The transmitter device according to claim 8 , wherein the signature sequences are sparse signature sequences.

10. The transmitter device according to claim 1 , wherein the error correction code is a turbo code or a convolutional code.

11. A receiver device for a wireless communication system, the receiver device comprising:

a receiver that receives a signal comprising modulated symbols associated with at least one shortened or extended code word having a code rate over a radio channel of the wireless communication system;

a memory comprising instructions; and

a processor coupled to the receiver and the memory, wherein the instructions cause the processor to:

demodulate the received signal to obtain a demodulated signal;

perform de-interleaving and de-rate matching based on a mother code rate (R M ) and a transmission code rate (R TX ) associated with at least one mother code word, wherein the R M comprises a ratio of a number of information bits divided by a number of coded bits, wherein the R TX comprises a ratio of the number of information bits divided by a total number of bits transmitted over resource elements used for data transmission, and wherein performing de-interleaving and de-rate matching based on the R M and the R TX comprises:

first de-rate matching the demodulated signal to obtain a de-rate matched demodulated signal and second de-interleaving the de-rate matched demodulated signal to obtain the mother code word when the code rate is larger than the R M of the mother code word for the shortened or extended code word; and

first de-interleaving the demodulated signal to obtain a de-interleaved demodulated signal and second de-rate matching the de-interleaved demodulated signal to obtain the mother code word when the code rate is not larger than the R M of the mother code word for the shortened or extended code word; and

decode the at least one code word to obtain information bits associated with the mother code word.

12. A transmission method in a wireless communication system, the method comprising:

receiving at least one stream of information bits;

encoding the at least one stream of information bits using at least one error correction code to obtain at least one mother code word having a mother code rate (R M );

perform interleaving and rate matching based on the R M and a transmission code rate (R TX ) associated with the at least one mother code word, wherein the R M comprises a ratio of a number of information bits divided by a number of coded bits, wherein the R TX comprises a ratio of the number of information bits divided by a total number of bits transmitted over resource elements used for data transmission, and wherein performing interleaving and rate matching based on the R M and the R TX comprises:

first interleaving the at least one mother code word to obtain an interleaved code word, and second rate matching the interleaved code word to obtain a shortened code word having a code rate that is higher than the R M when the R M is smaller than the R TX ; and

first rate matching the at least one mother code word to obtain an extended code word, and second interleaving the extended code word having a code rate that is lower than the R M when the R M is smaller than the R TX ;

modulating the shortened or extended code word to obtain modulated symbols; and

transmitting a signal comprising the modulated symbols over a radio channel of the wireless communication system.

13. The transmission method according to claim 12 , wherein the method further comprises interleaving the at least one mother code word or extended code word by a Low Density Spreading (LDS) matrix interleaver.

14. The transmission method according to claim 13 , wherein the method further comprises applying column permutation on elements of interleaver matrices.

15. The transmission method according to claim 13 , wherein the method further comprises adapting the LDS matrix interleaver size to different code rates associated with different streams of information bits for transmission.

16. The transmission method according to claim 13 , wherein the method further comprises adding dummy bits to the shortened or extended code word such that a code word length of the shortened or extended code word is a multiple of the number of columns of an interleaver matrix.

17. A receiving method in a wireless communication system, the method comprising:

receiving a signal comprising modulated symbols associated with at least one shortened or extended code word having a code rate over a radio channel of the wireless communication system;

demodulating the received signal to obtain a demodulated signal;

perform de-interleaving and de-rate matching based on a mother code rate (R M ) and a transmission code rate (R TX ) associated with at least one mother code word, wherein the R M comprises a ratio of a number of information bits divided by a number of coded bits, wherein the R TX comprises a ratio of the number of information bits divided by a total number of bits transmitted over resource elements used for data transmission, and wherein performing de-interleaving and de-rate matching based on the R M and the R TX comprises:

first de-rate matching the demodulated signal to obtain a de-rate matched demodulated signal and second de-interleaving the de-rate matched demodulated signal to obtain the mother code word when the code rate is larger than the R M of the mother code word for the shortened or extended code word; and

first de-interleaving the demodulated signal to obtain a de-interleaved demodulated signal and second de-rate matching the de-interleaved demodulated signal to obtain the mother code word when the code rate is not larger than the R M of the mother code word for the shortened or extended code word; and

decoding the mother code word to obtain information bits associated with the mother code word.