Combining QAM and QPSK to optimize license capacity in cellular, multipoint wireless access systems
US6650628B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Jul 9, 1999 |
| Grant date | Nov 18, 2003 |
| Priority date | — |
| Expiry date | Jul 9, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L27/0008
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A system and method for combining multiplexing and modulation schemes to deliver high and low bandwidth services over a wireless link. The system includes a base station (BTS) with a transmitter for point to multipoint communications to a plurality of network interface units (NIUs) located at customer locations within a geographic area serviced by the base station. In addition to receiving downstream communication from the BTS, each NIU is equipped to communicate in a point to point manner with the BTS. According to the invention time division multiple access multiplexing (TDMA) and quadrature phase shift key (QPSK) modulation is employed for low bandwidth services and frequency division multiplexing (FDM) and quadrature amplitude modulation (QAM) is used to supply high bandwidth services.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.