Code assignment algorithm for synchronous DS-CDMA links with SDMA using estimated spatial signature vectors
US7050480B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 24, 2001 |
| Grant date | May 23, 2006 |
| Priority date | — |
| Expiry date | Jun 8, 2024 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L1/0009
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A method is disclosed for operating a synchronous space division multiple access, code division multiple access communications system. The method operates, within a coverage area of a base station (BS) or radio base unit (RBU) having a multi-element antenna array, for estimating a SSV for individual ones of a plurality of active subscriber stations (SSs) and assigns a spreading code to a subscriber station (SS) that minimizes the similarity of the determined SSVs of the SSs in a spreading code set. A metric used to measure the similarity of the spatial signature vectors of the SSs comprises the squared sum of the inner products of same code SSs' SSV with a current SS's SSV. The step of assigning includes calculating the magnitude of the squared inner product of the SSVs of all pairs of active SSs; using the calculated values for determining ξn(c) for each spreading code that is not already used some specified maximum number of times; and assigning to a SS the spreading code with a minimum ξn(c).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.