Sub-banded ultra-wideband communications systems

• US 7,532,564 B2
• Filed: 09/11/2002
• Issued: 05/12/2009
• Est. Priority Date: 09/11/2002
• Status: Expired due to Fees

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Somayazulu, Srinivasa, Ho, Minnie, Foerster, Jeffrey R., Tinsley, Keith R.
• Primary Examiner(s): Moore, Jr.; Michael J
• Application Number:
  US10/241,889
• Publication Number:
  US 20040047285A1
• Time in Patent Office: 2,435 Days
• Field of Search: 370203-210
• US Class Current: 370/208
• CPC Class Codes: H04B 1/692 Hybrid techniques using combinations of two or more spread spectrum techniques
• CPC Class Codes: H04B 1/7163 using impulse radio
• CPC Class Codes: H04B 1/71632 Signal aspects H04B1/7172 and H04B1/7176 take precedence
• CPC Class Codes: H04B 1/719 Interference-related aspects
• CPC Class Codes: H04L 27/2601 Multicarrier modulation systems

Abstract

A sub-banded ultra-wideband (SB-UWB) system may combine aspects of an orthogonal frequency division multiplexing (OFDM) modulation scheme with aspects of an ultra-wideband system. In one embodiment, the system may use orthogonal waveforms to form an ultra-wideband wireless communications system. In another embodiment, an FFT based implementation of the system may be used to generate and detect an SB-UWB waveform.

Claims

1. A transmitter, comprising:

a wideband pulse modulator to modulate a data sequence onto a plurality of wideband pulses with a selected duty cycle, the duty cycle being selected for reception without equalization;

a plurality of sub-band filters each to generate a single sub-band of the wideband pulses, the sub-bands comprising concatenated orthogonal frequency division waveforms to each carry a portion of the data sequence;

a gate to receive the sub-bands, to separate the sub-bands in time for time diversity, to spread the data sequence across the wideband, and to attenuate sub-bands that experience interference; and

an upconverter to convert the sub-bands to radio-frequency bands for transmission.

2. The transmitter of claim 1, wherein the gate is to separate the sub-bands in time so that a single sub-band is transmitted at a time.

3. The transmitter of claim 1, wherein the gate is to attenuate sub-bands in proportion to the interference.

4. The transmitter of claim 1, wherein the gate is to attenuate sub-bands by not using any sub-band in which there is strong narrowband interference.

5. The transmitter of claim 4, wherein the gate overlays the wideband pulses on top of narrowband interference.

6. The transmitter of claim 1, wherein the gate includes a radio-frequency switch that operates at the pulse repetition rate.

7. The transmitter of claim 6, wherein the pulse repetition rate is a function of a desired transmit data rate.

8. The transmitter of claim 1, wherein the wideband pulse modulator utilizes direct sequence spreading on sub-bands of the sub-banded ultra-wideband waveform.

9. The transmitter of claim 1, wherein the wideband pulse modulator and the sub-band filters are comprised of a fast-Fourier transform structure to generate the sub-banded ultra-wideband waveform.

10. The transmitter of claim 1, wherein the gate comprises a multiple-gated, phased-carrier structure to generate the sub-banded ultra-wideband waveform.

11. The transmitter of claim 1, wherein the wideband pulse modulator is configured to utilize frequency-shift keying on sub-bands of the sub-banded ultra-wideband waveform.

12. A method comprising:

modulating a data sequence onto a plurality of wideband pulses with a selected duty cycle, the duty cycle being selected for reception without equalization;

filtering the plurality of wideband pulses with a plurality of sub-band filters each to generate a single sub-band of the wideband pulses, the sub-bands comprising concatenated orthogonal frequency division waveforms to each carry a portion of the data sequence;

separating the sub-bands in time for time diversity;

spreading the data sequence across the wideband;

attenuating sub-bands that experience interference; and

converting the sub-bands to radio-frequency bands for transmission.

13. The method of claim 12, wherein separating comprises separating the sub-bands in time so that a single sub-band is transmitted at a time.

14. The method of claim 12, wherein attenuating comprises attenuating sub-bands in proportion to the interference.

15. The method of claim 12, further comprising direct sequence spreading the data sequence on sub-bands of the sub-banded ultra-wideband waveform.

16. The method of claim 12, further comprising time-hopping on sub bands of the sub-banded ultra-wideband waveform.

17. The method of claim 12, further comprising frequency-shift-keying on sub-bands of the sub-banded ultra-wideband waveform.

18. The method of claim 12, further comprising frequency-hopping on sub-bands of the sub-banded ultra-wideband waveform.