06901112 is referenced by 84 patents and cites 140 patents.

An ultra wide bandwidth, high speed, spread spectrum communications system uses short wavelets of electromagnetic energy to transmit information through objects such as walls or earth. The communication system uses baseband codes formed from time shifted and inverted wavelets to encode data on a RF signal. Typical wavelet pulse durations are on the order of 100 to 1000 picoseconds with a bandwidth of approximately 8 GHz to 1 GHz, respectively. The combination of short duration wavelets and encoding techniques are used to spread the signal energy over an ultra wide frequency band such that the energy is not concentrated in any particular narrow band (e.g. VHF: 30-300 MHz or UHF: 300-1000 MHz) and is not detected by conventional narrow band receivers so it does not interfere with those communication systems. The use of pulse codes composed of time shifted and inverted wavelets gives the system according to the present invention has a spatial resolution on the order of 1 foot which is sufficient to minimize the negative effects of multipath interference and permit time domain rake processing.

Title
Ultra wide bandwidth spread-spectrum communications system
Application Number
10/259736
Publication Number
6901112 (B2)
Application Date
September 30, 2002
Publication Date
May 31, 2005
Inventor
Martin Rofheart
Washington
DC, US
John W McCorkle
Vienna
VA, US
Agent
Posz Law Group
Assignee
Freescale Semiconductor
TX, US
IPC
H04L 027/00
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