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 a 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.