Subscriber unit for wireless digital telephone system
US4825448A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 7, 1986 |
| Grant date | Apr 25, 1989 |
| Priority date | — |
| Expiry date | Aug 7, 2006 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03D2200/0082
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A digital wireless subscriber telephone unit for wireless connection with a base station. The subscriber unit has baseband processor which is coupled to storage means for the baseband functions. The baseband processor is direct access coupled to a modem processor whereby the two processors may communicate with each other. The modem processor generally acts as the master in the system, although lock-out means may be used in certain circumstances. The signal from the modem processor is converted to an analog signal, which is subjected to deglitching, and the deglitched signal is then upconverted and filtered to form an IF signal which is thereafter amplified. The amplified IF signal is combined with a signal generated by a synthesizer to provide an RF signal. On the basis of certain signals received from the base station, the baseband processor produces initiating signals which determine whether the subscriber unit will be in the transmit mode or the receive mode. In intervals between actuation of the system, a training mode is used wherein a known signal from the modem processor is compared with a looped-back signal to produce correction constants to compensate for undersirable vari…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.