Ultra-wideband communication systems and methods

• US 20050047367A1
• Filed: 10/08/2004
• Published: 03/03/2005
• Est. Priority Date: 12/06/2001
• Status: Active Grant

• Current Assignee: Intellectual Ventures Holding 81 LLC (Intellectual Ventures LLC)
• Original Assignee: Pulse-Link Incorporated
• Inventors: Lakkis, Ismail
• Granted Patent: US 7,349,439 B2
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04B 1/71632 Signal aspects H04B1/7172 and H04B1/7176 take precedence
• CPC Class Codes: H04B 1/71635 Transmitter aspects H04B1/7174 takes precedence
• CPC Class Codes: H04B 1/7176 Data mapping, e.g. modulation
• CPC Class Codes: H04B 1/719 Interference-related aspects
• CPC Class Codes: H04B 7/0669 using different channel coding between antennas space-time coding H04L1/0618
• CPC Class Codes: H04B 7/068 using space frequency diversity space-frequency coding H04L1/0606
• CPC Class Codes: H04B 7/08 at the receiving station
• CPC Class Codes: H04B 7/12 Frequency diversity

Abstract

Systems and methods of ultra-wideband communication are provided. In one ultra-wideband communication method, a communication channel is divided into a plurality of non-overlapping sub-channels by dividing a single serial message intended for an ultra-wideband communication device into a plurality of parallel messages. Each of the plurality of parallel messages are then encoded onto at least some of the plurality of sub-channels, and then transmitted. This Abstract is provided for the sole purpose of complying with the Abstract requirement rules that allow a reader to quickly ascertain the subject matter of the disclosure contained herein. This Abstract is submitted with the explicit understanding that it will not be used to interpret or to limit the scope or the meaning of the claims.

Claims

1. A method of ultra-wideband communication, the method comprising the steps of:

generating an ultra-wideband communication channel comprising a radio frequency band segmented into a plurality of non-overlapping sub-channels;

dividing a single serial message into a plurality of parallel messages;

encoding each of the plurality of parallel messages onto at least some of the plurality of sub-channels; and

transmitting the plurality of parallel messages over the ultra-wideband communication channel.

2. The method of claim 1, wherein the step of transmitting the plurality of parallel messages over the ultra-wideband channel comprises transmitting a plurality of discrete electromagnetic pulses, with each pulse having a duration that can range between about 10 picoseconds to about 1 microsecond.

3. The method of claim 1, wherein the step of transmitting the plurality of parallel messages over the ultra-wideband channel comprises transmitting a plurality of discrete electromagnetic pulses, with each pulse occupying more than 500 megahertz of a radio frequency spectrum.

4. The method of claim 2, wherein each of the discrete electromagnetic pulses has a power that can range between about +30 dBm to about −

60 dBm, as measured at a single frequency.

5. The method of claim 1, wherein each of the plurality of non-overlapping sub-channels occupies a discrete portion of the radio frequency band.

6. A method of ultra-wideband communication, the method comprising the steps of:

generating an ultra-wideband communication channel comprising a radio frequency channel segmented into a plurality of non-overlapping sub-channels;

dividing a plurality of serial messages into a plurality of parallel messages;

encoding each of the plurality of parallel messages onto at least some of the plurality of sub-channels; and

transmitting the plurality of parallel messages over the ultra-wideband communication channel.

7. The method of claim 6, wherein the plurality of parallel messages are transmitted to a plurality of ultra-wideband communication devices.

8. The method of claim 6, further comprising a base station that dynamically assigns specific non-overlapping sub-channels to each of a plurality of ultra-wideband communication devices.

9. The method of claim 8, wherein the base station assigns the non-overlapping sub-channels to an ultra-wideband communication device based at least in part on a signal-to-interference measurement received from each of the plurality of communication devices.

10. The method of claim 6, wherein each of the plurality of non-overlapping sub-channels occupies a discrete portion of the radio frequency band.

11. The method of claim 6, further comprising the steps of:

organizing a plurality of sub-channels into several sub-channel groups;

receiving a signal-to-interference measurement from each of a plurality of ultra-wideband communication devices for each sub-channel group;

comparing each signal interference measurement to a threshold value; and

assigning the sub-channel groups to specific ultra-wideband communication devices based on a comparison of the signal interference ratio measurements to the threshold value.

12. The method of claim 7, further comprising the steps of:

generating a bit stream for each non-overlapping sub-channel;

shifting each bit stream in radio frequency by a radio frequency offset associated with each non-overlapping sub-channel;

summing the shifted bit streams to generate a signal that occupies substantially all of the radio frequency band; and

transmitting the signal to each of the plurality of ultra-wideband communication devices.

13. The method of claim 6, wherein each sub-channel comprises a radio frequency bandwidth that is defined by:

b=(1+r)/T

where b=a radio frequency bandwidth for each of the plurality of sub-channels, and r=a roll-off factor, and T=a symbol duration for each of the plurality of non-overlapping sub-channels.

14. The method of claim 13, wherein the roll-off factor is selected so that M is approximately an integer in:

M=N(1+r)

15. A method for generating a plurality of synchronization codes for use in an ultra-wideband communication system, the method comprising the steps of:

selecting a synchronization code sequence;

generating a first synchronization code by repeating the synchronization code sequence a number of times equal to a reuse factor; and

generating subsequent synchronization codes by shifting the first synchronization code in frequency.

16. The method of claim 15, wherein shifting the first synchronization code in frequency is achieved using the following equation:

z^r(m)=y(m)*exp(j*2*π

*r*m/(n*L)), where;

where;

r=1 to L, L being the length of the synchronization code sequence being used to generate the subsequent synchronization codes;

z^r(m)=each subsequent synchronization code sequence;

y(m)=the first synchronization code sequence;

n=the number of times the synchronization code sequence is repeated; and

m=0 to n*L−

1.

17. An ultra-wideband communication system, comprising:

a plurality of base stations configured to communicate with a plurality of ultra-wideband communication devices over a common communication channel, with each base station configured to use a unique synchronization code relative to other adjacent base stations when communicating with the plurality of ultra-wideband communication devices over the common communication channel, with the common communication channel comprising a radio frequency bandwidth that is divided into a plurality of non-overlapping sub-channels.

18. The ultra-wideband communication system of claim 17, wherein the synchronization codes have at least one ideal cross correlation property relative to each other.

19. The ultra-wideband communication system of claim 17, where the system is configured to use a synchronization code reuse factor of 4.