Sub-banded ultra-wideband communication system

• US 20060153279A1
• Filed: 02/10/2004
• Published: 07/13/2006
• Est. Priority Date: 02/14/2003
• Status: Active Grant

• Current Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Original Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Birru, Dagnachew
• Granted Patent: US 7,764,725 B2
• 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 1/713 using frequency hopping
• CPC Class Codes: H04B 1/715 Interference-related aspects
• 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: H04B 2001/7154 with means for preventing interference

Abstract

A wireless communication system performs high-speed transmission of information signals by using a multi-band approach. Each band spans about 500 MHz. A flexible modulation scheme within each band employs time, amplitude and phase modulations, allowing adaptation of the data rate to the sub-band conditions. In addition, pseudo-random frequency sequence is employed to provide sufficient multi-user interference reduction.

Claims

1. A method for transmitting data using ultra-wideband techniques, said method comprising the steps of:

(a) providing a transmitter subsystem configured to perform the steps of—

(a.1) providing a UWB channel as a series of UWB signal pulses,

(a.2) dividing the UWB channel into N bands, and

(a.3) transmitting each pulse of said series through a band of said N divided bands;

(b) providing a receiver subsystem configured to perform the steps of—

(b.1) receiving a UWB signal divided into N bands,

(b.2) combining the N bands into a UWB channel, and

(b.3) deriving a series of UWB pulses from the combined N bands.

2. The method claim 1, wherein said dividing step (a.2) further comprises the step of (a.2.1) dividing said UWB channel such that the span of each band is about equal.

3. The method of claim 1, further comprising the step of (a.4) modulating said series of UWB pulses using at least one modulation technique selected from the group consisting of time/phase, frequency, and amplitude.

4. The method of claim 3, wherein said modulating step (c) further comprises the step of (a.4.1) employing a pseudo-random noise frequency sequence to provide sufficient multi-user interference reduction.

5. The method of claim 3, wherein said transmitting step (a.3) further comprises the steps of:

(a.3.1) transmitting the provided a first pulse of the series through a 3.2 to 3.7 GHz band of said N bands; and

(a.3.2) transmitting any pulse other than said first pulse of the series in non-first band of said N bands.

6. The method of claim 1, wherein when N>

3 said transmitting step (a.3) optionally further comprises the step of (a.3.3) skipping at least one in-between band of said N bands.

7. The method of claim 3, further comprising the step of (a.5) carrying the multi-band transmission in a time multiplexed manner such that an inter-pulse separation is maximized.

8. The method of claim 1, when N=2 further comprising the steps of:

(a.6) carrying 20 Mb/s by a first band; and

(a.7) carrying 30 Mb/s by a second band.

9. The method of claim 1, further comprising the step of (a.8) allocating data rate per band based on at least one of requirements of an application and capacity of a sub-channel.

10. The method of claim 9, further comprising the steps of:

(a.9) carrying by a first band of said N bands of 2 bits per symbol;

(a.10) carrying by a second band of said N bands of 4 bits per symbol.

11. The method of claim 9, further comprising the step of (a.11) allocating a resource based on requirements of an application, wherein the resource is at least one of number of bands, modulations, symbol rate/band, raw bit rate, symbol interval, and inter-pulse separation.

12. The method of claim 11, further comprising the step of (a.12) allocating n bits per symbol per channel, wherein m are carried via position and n-m are carried via amplitude/phase.

13. An apparatus for a multi-band ultra-wideband (UWB) communication system, comprising:

a transmitter subsystem comprising—

a controller configured to divide a UWB channel into N bands,

a modulator configured to provide a sequence of modulated pulses, and

a transmitter configured transmits each modulated pulse through one of said N bands; and

a receiver subsystem comprising—

a receiver configured to receive UWB signals transmitted through said N bands,

a controller configured to combine into a sequence of modulated pulses the signals received, and

a demodulator configured to demodulate the sequence of modulated pulses.

14. The apparatus of claim 13, wherein:

said transmitter further comprises means for sending selected from the group consisting of an antenna, a cable, and an integrated circuit (IC) functioning as an antenna; and

said receiver further comprises means for receiving selected from the group consisting of an antenna, a cable, and an integrated circuit (IC) functioning as an antenna.

15. The apparatus of claim 13, wherein the span of each of said N bands is about equal.

16. The apparatus of claim 13, further comprising:

a pseudorandom frequency sequence input to said modulator to provide sufficient multi-user interference reduction.

17. The apparatus of claim 13, wherein the output of the transmitter is described by the equation

$y$

( t ) = ∑

n ⁢

a n ⁢

h l ⁡

( t - nT - c n ⁢

τ

, f ⁡

( n ) ) + b n ⁢

h l ⁡

( t - nT - c n ⁢

τ

- d n ⁢

τ

ch , f ⁡

( n ) )

where

a_n and b_n are an amplitude or phase modulating data,

c_n and d_n are a differential time modulation data,

f(n) is a frequency band component,

τ

_ch is a small time unit for channelization purposes or an additional channel to convey data,

τ

is a small time unit for position modulation, and

T is an inter-pulse separation.

18. The apparatus of claim 17, wherein the multi-band transmission is carried in a time multiplexed manner such that the inter-pulse separation T is maximized.