Dual mode transmitter and receiver
US5291516A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 18, 1992 |
| Grant date | Mar 1, 1994 |
| Priority date | — |
| Expiry date | Sep 18, 2012 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04W88/06
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A dual-mode transmitter having an antenna, a mode controller, a source encoder, a tunable-frequency synthesizer, a chip-code generator, a spread-spectrum modulator, a narrowband modualator, a power amplifier, and an adjustable bandpass filter. Also provided is a dual-mode receiver having a mode controller, a tunable-frequency synthesizer, a chip-code generator, an antenna, an adjustable bandpass filter, a preamplifier, a frequency converter, an IF amplifier, a spread-spectrum despreader, a spread-spectrum demodulator, a narrowband modulator, and a source decoder. For the transmitter and receiver, the mode controller selects receiving a narrowband modulation or a spread-spectrum modulation. The tunable-frequency synthesizer generates a local oscillator signal for the receiver, and a carrier signal for the transmitter. The chip-code generator generates a chip code signal for both the transmitter and the receiver. With a narrowband modulation setting of the mode controller, the transmitter and receiver have the adjustable bandpass filters adjusted to a narrowband width for telephone communications. With a spread-spectrum setting of the mode controller, the adjustable bandpass filters …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.