Arbitrary waveform modem
US6396801B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 22, 1998 |
| Grant date | May 28, 2002 |
| Priority date | — |
| Expiry date | Jul 22, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04J14/007
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
An improved communication system which provides improved spectral efficiency as well as relatively low co-channel interference modulation characteristics relative to known communication systems. In particular, the communication system includes a modem that includes an arbitrary or chaotic waveform generator and a chaotic waveform demodulator configured as a sliding window correlator that is adapted to modulate and demodulate an arbitrary or chaotic waveforms. The modulator includes a finite impulse response (FIR) filter, for example, formed from tapped delay lines with unequal time delays. The demodulator is formed as a matched filter for recovery of the input data signals. The modem is adapted to transmit either optical or RF waveforms. In order to prevent drift of the tap weights due to temperature drift of the tapped delay lines and other factors, a closed servo loop may be provided for each tap weight. By maintaining the accuracy of the tap weights, the system in accordance with the present invention is adapted to provide arbitrary or chaotic modulation and demodulation of the input data signal thereby providing increased spectral efficiency and improved performance which provi…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.