Direct conversion time division duplex radio, direct sequence spread spectrum cordless telephone
US6411646B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 30, 1998 |
| Grant date | Jun 25, 2002 |
| Priority date | — |
| Expiry date | Jun 30, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B1/408
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A wireless transceiver comprises a digital to analog converter having an input for receiving a digital representation of a direct sequence spread spectrum signal and having an analog output. A bandpass or lowpass filter has an input coupled to the analog output of the digital to analog converter and has a filtered output. An adder has a first input coupled to the filtered output and a second input coupled to a loop control voltage generated by a phase lock loop. The adder produces a summed output. A VCO integrated into the phase lock loop has a control input coupled to the summed output. An RF output of the VCO produces a continuous phase frequency shift keyed spread spectrum signal in response to the digital representation of the direct sequence spread spectrums signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.