Data transmission and reception method and apparatus

• US 7,573,805 B2
• Filed: 12/28/2001
• Issued: 08/11/2009
• Est. Priority Date: 12/28/2001
• Status: Active Grant

• Current Assignee: Motorola Solutions, Inc.
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Zhuang, Xiangyang, Vook, Frederick W., Thomas, Timothy A.
• Primary Examiner(s): Sheikh; Ayaz R
• Assistant Examiner(s): Ho; Chuong T
• Application Number:
  US10/035,027
• Publication Number:
  US 20030123381A1
• Time in Patent Office: 2,783 Days
• Field of Search: 370208-210, 370/203, 370/204, 370/206, 370/480, 370/481, 370/482, 370/310, 370/319, 370/329, 370/343, 370/344, 375/267, 455/92, 714/746
• US Class Current: 370/208
• CPC Class Codes: H04B 7/04 using two or more spaced independent antennas
• CPC Class Codes: H04B 7/0613 using simultaneous transmission H04B7/0686 takes precedence
• CPC Class Codes: H04B 7/0837 using pre-detection combining H04B7/0868 takes precedence
• CPC Class Codes: H04L 5/0023 Time-frequency-space

Abstract

A datastream of bits (which may itself be comprised of a plurality of datastreams as derived from a plurality of sources) are coded (21) and then interleaved (12) across a plurality of transmitters (25 and 26) and a plurality of subcarriers (27) as supported and shared by the transmitters. If desired, the bits can be mapped to corresponding symbols prior to transmission. The resultant information is transmitted simultaneously by the transmitters using the shared channel of subcarriers. Upon reception, the received signals are de-interleaved and decoded to recover the original datastream for each sources.

Claims

1. A method of transmitting data comprising:

providing a datastream comprised of bits;

interleaving the bits of the datastream across a plurality of orthogonal frequency division multiplexed radio frequency transmitters, wherein each of the radio frequency transmitters transmits a plurality of radio frequency subcarriers, to provide interleaved bits wherein consecutive interleaved bits are grouped and mapped to symbols and the symbols assigned for transmission such that adjacent datastream bits are assigned to differing transmitters and differing subcarriers with low channel response correlation to thereby exploit an increased amount of spatial and frequency diversity;

transmitting the symbols using the plurality of radio frequency subcarriers of the plurality of orthogonal frequency division multiplexed radio frequency transmitters wherein assigning symbols such that adjacent datastream bits are assigned to differing transmitters and differing subcarriers with low channel response correlation further comprises assigning symbols such that adjacent datastream bits out of each encoder when multiple encoders are used are assigned to differing transmitters and different subcarriers with low channel response correlation to thereby exploit an increased amount of spatial and frequency diversity for each encoded datastream.

2. The method of claim 1 wherein providing a datastream comprised of bits includes providing a datastream comprised of bits as provided from a single source.

3. The method of claim 1 wherein providing a datastream comprised of bits includes providing a datastream comprised of bits as provided from a plurality of sources.

4. The method of claim 3 wherein providing a datastream comprised of bits as provided from a plurality of sources includes providing a datastream comprised of bits as provided from a plurality of sources wherein at least some of the bits as provided from at least one of the plurality of sources are encoded bits.

5. The method of claim 1 wherein providing a datastream comprised of bits includes providing a datastream comprised of encoded bits.

6. The method of claim 5 wherein providing a datastream comprised of encoded bits includes providing a datastream comprised of convolutionally encoded bits.

7. The method of claim 5 wherein providing a datastream comprised of encoded bits includes providing a datastream comprised of serially concatenated convolutionally encoded bits.

8. The method of claim 5 wherein providing a datastream comprised of encoded bits includes providing a datastream comprised of parallel concatenated convolutionally encoded bits.

9. A method of receiving data comprising:

using at least one orthogonal frequency division multiplexed transmission receiver having at least one antenna to receive multi-antenna transmission signals across a plurality of subcarriers;

demodulating the received multi-antenna transmission signals to recover data bits from bit metrics computed by using a maximum likelihood bit soft information estimator represented by

10. A method of receiving data comprising:

using at least one orthogonal frequency division multiplexed transmission receiver having at least one antenna to receive multi-antenna transmission signals across a plurality of subcarriers;

demodulating the received multi-antenna transmission signals to recover data bits from bit metrics computed by using a zero forcing bit metric estimator represented by

11. A method of receiving data comprising:

using at least one orthogonal frequency division multiplexed transmission receiver having at least one antenna to receive multi-antenna transmission signals across a plurality of subcarriers;

demodulating the received multi-antenna transmission signals to recover data bits from bit metrics computed by using a minimum mean squared error bit metric estimator represented by

12. A method of receiving data comprising:

substantially simultaneously;

using a first orthogonal frequency division multiplexed transmission receiver having at least one antenna to receive multi-antenna transmission signal across a plurality of subcarriers to obtain first modulation items;

using a second orthogonal frequency division multiplexed transmission receiver having at least one antenna to receive multi-antenna transmission signal across a plurality of subcarriers to obtain second modulation items, wherein the plurality of subcarriers are substantially identical for both the first and second receiver;

demodulating the radio frequency transmissions as received by the first and second receivers to recover a single stream of data comprised of bits that are recovered from both the first and second modulation items, wherein demodulation includes the use of a zero forcing symbol metric estimator based on (“

ln”

stands for the natural logarithm)

13. A method of receiving data comprising:

substantially simultaneously;

using a first orthogonal frequency division multiplexed transmission receiver having at least one antenna to receive radio frequency transmissions across a plurality of subcarriers to obtain first modulation items;

using a second orthogonal frequency division multiplexed transmission receiver having at least one antenna to receive radio frequency transmissions across a plurality of subcarriers to obtain second modulation items, wherein the plurality of subcarriers are substantially identical for both the first and second receiver;

demodulating the radio frequency transmissions as received by the first and second receivers to recover a single stream of data comprised of bits that are recovered from both the first and second modulation items, wherein demodulation includes the use of a minimum mean squared error symbol metric estimator based on (“

ln”

stands for the natural logarithm)