Granted Patent B2

US 8,873,678 · App. 12/939,327 · Granted Oct 28, 2014

Abstract

Claims (31)

1. A method, comprising:

encoding data of a data stream according to a space time transmit diversity scheme, the encoding comprising:

encoding consecutive data symbols of the data stream in time, wherein the consecutive data symbols are mapped multiple times to different instants of time; and

encoding the consecutive data symbols of the data stream in space, wherein the consecutive data symbols are mapped from the data stream to multiple data streams; and

spatial-multiplexing the encoded data, the spatial-multiplexing comprising:

after encoding the consecutive data symbols in time and in space, precoding the encoded data symbols based on multiple linearly independent precoding vectors.

2. The method of claim 1 , wherein the space time transmit diversity scheme is based on an Alamouti code.

3. The method of claim 1 , wherein spatial-multiplexing the encoded data comprises precoding the encoded data using two linearly independent precoding vectors.

4. The method of claim 3 , wherein the two linearly independent precoding vectors are orthogonal to each other.

5. The method of claim 3 , wherein each one of the linearly independent precoding vectors comprises a first weight and a second weight.

6. The method of claim 5 , wherein the first weight and the second weight are constant over time.

7. The method of claim 5 , wherein the first weight is constant over time and the second weight is variable over time.

8. The method of claim 3 , wherein the encoded data comprises a first data stream which is processed using a first one of the linearly independent precoding vectors and a second data stream which is processed using a second one of the linearly independent precoding vectors.

9. The method of claim 3 , further comprising:

receiving data comprising a channel quality indication and two linearly independent vectors; and

generating the precoding vectors on the basis of the information comprised in the received data.

10. The method of claim 1 , wherein the encoded data comprises a first data stream and a second data stream.

11. The method of claim 1 , further comprising at least one of:

spreading the encoded data using a spreading code and scrambling the encoded data using a scrambling code.

12. The method of claim 1 , further comprising:

transmitting the encoded and spatial-multiplexed data over a first antenna and a second antenna.

13. A transmitter, comprising:

a first unit to encode data of a data stream according to a space time transmit diversity scheme, the encoding comprising:

encoding consecutive data symbols of the data stream in time, wherein the consecutive data symbols are mapped multiple times to different instants of time; and

encoding the consecutive data symbols of the data stream in space, wherein the consecutive data symbols are mapped from the data stream to multiple data streams; and

a second unit to spatial-multiplex encoded data, wherein the transmitter is configured to operate in an operating mode in which data is processed by the first unit and the second unit, the spatial-multiplexing comprising:

after encoding the consecutive data symbols in time and in space, precoding the encoded data symbols based on multiple linearly independent precoding vectors.

14. The transmitter of claim 13 , wherein the space time transmit diversity scheme is based on an Alamouti code.

15. The transmitter of claim 13 , wherein the spatial-multiplexing of data comprises precoding the data using two linearly independent precoding vectors.

16. The transmitter of claim 13 , further comprising at least one of:

a spreading unit to generate spread data and a scrambling unit to generate scrambled data, either or both in conjunction with the spatial-multiplexing of the encoded data.

Assignments (6)