Adaptive radio frequency (RF) filter
US7835434B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 21, 2002 |
| Grant date | Nov 16, 2010 |
| Priority date | — |
| Expiry date | Jul 4, 2027 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L27/2601
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
The invention relates to an adaptive Radio Frequency (RF) filter (11), which is particularly useful as an RF filter in Wireless Local Area Networks (WLAN's). As greater demands are placed on RF systems, for example in WLAN's in order to increase channel capacity by utilizing available bandwidth, corresponding demands are placed upon performance and tolerance of components used in FR circuits. An adaptive Radio Frequency (RF) filter for filtering first and second RF signals from an OFDM encoded carrier signal is provided, the adaptive RF filter comprises: a low-pass filter (102) configured to filter first and second RF signals, one from another, so as to provide a first RF output signal; the adaptive RF filter being tunable in response to one or more input signals, the at least one input signal being derived from a comparator (37,100), which compares the first RF output signal with a desired value for said first RF output signal, and provides a connection factor for varying a characteristic of the filter (102). An advantage of the invention is that it facilitates filter of two OFDM encoded RF signals, the first typically at 8.1 MHz and the second (unwanted) at 11.9 MHz, from a base-…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.