AM compatible digital waveform frame timing recovery and frame synchronous power measurement
US5764706A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 22, 1996 |
| Grant date | Jun 9, 1998 |
| Priority date | — |
| Expiry date | Apr 22, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04H2201/20
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
In a broadcast system having a complex waveform of digital and analog segments, frame timing is recovered and the frame synchronous power of the digital portion of the composite AM compatible Digital Audio Broadcast (DAB) waveform is measured by examining a portion of the signal. The frame timing necessary for proper demodulation is recovered from the received signal, and a signal power measurement for scaling is provided. The composite AM compatible DAB waveform is produced by a modulation method in which a digital representation of an audio signal is encoded together with an analog amplitude modulated (AM) signal and transmitted simultaneously in the same frequency channel.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.