Methods and apparatus for wireless communication using orthogonal frequency division multiplexing
US7020071B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Nov 25, 1998 |
| Grant date | Mar 28, 2006 |
| Priority date | — |
| Expiry date | Jan 5, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L5/143
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
Methods and apparatus for wireless communication in systems such as omni-beam and narrow-beam fixed wireless loop (FWL) systems. In a first technique in accordance with the invention, referred to as code division duplex (CDD) time-slotted CDMA, uplink and downlink portions of the system are separated using code division duplexing, while the users within a given cell are also separated using codes, e.g., using time-slotted CDMA. In a second technique in accordance with the invention, referred to as time division duplex (TDD) time-slotted CDMA, uplink and downlink portions of the system are separated using time division duplexing, e.g., time slots, while the users in a given cell are separated using codes, e.g., time-slotted CDMA. Both the CDD and TDD techniques may make use of an electronically-steered beam which is designed to provide simultaneous coverage within a given cell for two or more users separated by codes. In a third technique in accordance with the invention, referred to as orthogonal frequency division multiplexing (OFDM), uplink and downlink portions of the system are separated in frequency, while the users are, e.g., also separated in frequency.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.