System and method for unified channelization for multi-band OFDM

• US 20050190817A1
• Filed: 02/07/2005
• Published: 09/01/2005
• Est. Priority Date: 02/09/2004
• Status: Abandoned Application

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Batra, Anuj, Ho, Jin-Meng, Balakrishnan, Jaiganesh
• Application Number:
  US11/053,306
• Publication Number:
  US 20050190817A1
• Time in Patent Office: Days
• US Class Current: 375/130
• CPC Class Codes: H04B 1/692 Hybrid techniques using combinations of two or more spread spectrum techniques
• CPC Class Codes: H04B 1/71632 Signal aspects H04B1/7172 and H04B1/7176 take precedence
• CPC Class Codes: H04L 5/023 Multiplexing of multicarrier modulation signals multicarrier modulation H04L27/2601
• CPC Class Codes: H04W 72/0446 Resources in time domain, e.g. slots or frames
• CPC Class Codes: H04W 72/0453 Resources in frequency domain, e.g. a carrier in FDMA
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks

Abstract

A system and method for channelization and data multiplexing in ultra-wideband (UWB) wireless communication system is described. The spectrum allocated for UWB in a multi-bank OFDM (orthogonal frequency division multiplex) system is subdivided into various bands. A set of time frequency codes (TFC'"'"'s) is defined, wherein each code specifies one of a plurality of unique band versus time sequences for a particular band group, for sequential data symbols of a given piconet. The combination of FDMA and TFC'"'"'s provides a data complexing system supporting up to 30 simultaneously operating piconets, and a simplified interface between the MAC and PHY.

Claims

1. A method of communication in a wireless network using ultra-wideband (UWB) spectrum, the wireless network comprising one or more simultaneously operating pico networks, the method comprising:

dividing the UWB spectrum into a plurality of frequency bands;

forming at least four band groups each including at least three frequency bands, and at least one band group including at least two frequency bands;

assigning at least one band group to each one of the pico networks;

assigning at least one time frequency code to symbols associated with each one of the pico networks, wherein the time frequency code represents one of a single frequency band and a pre-defined sequencing across all the frequency bands within the assigned band group;

communicating data within each one of the pico networks using the assigned band groups according to the time frequency code, wherein

each one of the band groups including at least three frequency bands further includes at least seven time frequency codes and the band group including at least two frequency bands further includes at least two time frequency codes.

2. A method according to claim 1, wherein at least four of the seven time frequency codes within each one of the band group, including at least three frequency bands, are time-varying time-frequency codes configured to use each one of the frequency band within the band group for associated successive symbols of corresponding pico network.

3. A method according to claim 1, wherein the time frequency codes within each one of the band group, including at least two frequency bands, are static time frequency codes assigned to a predetermined frequency band within the band group for associated successive symbols of corresponding pico network.

4. A method according to claim 1, wherein each frequency band is 528 MHz wide.

5. A method according to claim 4, wherein a center frequency of each frequency band is given by:

FC(N)=3432+528*(N−

1)MHz,

wherein FC(N) is the center frequency of band N.

6. A method according to claim 1, further comprising:

assigning a preamble to each one of the pico networks.

7. A method according to claim 5, wherein

the UWB spectrum includes at most fourteen frequency bands.

8. A system for channelization of ultra-wideband (UWB) spectrum in a wireless network using ultra-wideband (UWB) spectrum, the wireless network comprising one or more simultaneously operating pico networks, the system comprising

a frequency-synthesized oscillator configured to generate a signal in steps of 528 MHz beginning at center frequency of 3432 MHz and ending at center frequency of 10,296 MHz;

and

a time frequency code generator coupled to the frequency-synthesized oscillator and configured to assign time-frequency codes to successive data symbols of a pico network such that the successive data symbols are transmitted in corresponding frequency bands of a band group according to assigned time-frequency codes, wherein

the UWB spectrum comprises at least four band groups each including at least three frequency bands, and at least one band group including at least two frequency bands, and

each one of the band groups including at least three frequency bands further includes at least seven time frequency codes and the band group including at least two frequency bands further includes at least two time frequency codes

9. A system according to claim 8, wherein the time frequency generator assigns the time-frequency codes to the data symbols according to the time frequency code and a band group number assigned to the corresponding pico network.

10. A system according to claim 8, wherein at least four of the seven time frequency codes within each one of the band group, including at least three frequency bands, are time-varying time-frequency codes configured to use each one of the frequency band within the band group for associated successive symbols of corresponding pico network.

11. A system according to claim 8, wherein the time frequency codes within each one of the band group, including at least two frequency bands, are static time frequency codes assigned to a predetermined frequency band within the band group for associated successive symbols of corresponding pico network.

12. A system according to claim 8, wherein each frequency band is 528 MHz wide.

13. A system according to claim 12, wherein a center frequency of each frequency band is given by:

FC(N)=3432+528*(N−

1)MHz,

wherein FC(N) is the center frequency of band N.

14. A system according to claim 8, further comprising:

a data coding circuit coupled to the frequency-synthesized oscillator and configured to add convolutional error correcting codes to incoming data symbol, interleave across at most 1200 coded data bits and map onto data symbols;

an orthogonal frequency division multiplex (OFDM ) modulator coupled to the data coding circuit and configured to modulate the at most 100 data symbols onto at most 110 tones at 4.125 MHz spacing to create a baseband OFDM signal from DC to 528 MHz; and

a frequency multiplier coupled to the frequency-synthesized oscillator and configured to frequency shift the baseband OFDM signal one of the frequency bands.

15. A system according to claim 8, wherein the time frequency code generator generates time-frequency codes mapping to a unique preamble using a the time frequency code and a band group number such that successive symbols are transmitted in one or more frequency bands of the assigned band group.

16. A system according to claim 15, wherein the time frequency code generator is configured to generate an octet of data including at least three consecutive bits representing the band group and at least three consecutive bits representing the time frequency code.

17. A system according to claim 16, wherein band group and the time frequency code define a channel number.

18. A system according to claim 16, wherein the system is configured to determine a channel by masking the at least three consecutive bits of the octet representing the band group to determine the band group and masking the at least three consecutive bits of the octet representing the time frequency code to determine the time frequency code.