Error vector magnitude selection diversity metric for ofdm

A standard and measured technology, applied in the direction of space transmit diversity, diversity/multi-antenna system, transmission monitoring, etc., can solve problems such as low throughput and waiting time, reduced signal quality, and cannot be considered

Active Publication Date: 2006-11-15
CISCO TECH INC
View PDF2 Cites 9 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

For example, RSSI values ​​do not take into account factors such as multipath that can significantly degrade signal quality
[0017] Using RSSI to select the "best" antenna may result in lower throughput and latency than using a signal quality metric instead of a signal strength metric for selection

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Error vector magnitude selection diversity metric for ofdm
  • Error vector magnitude selection diversity metric for ofdm
  • Error vector magnitude selection diversity metric for ofdm

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0036] A selection diversity method and apparatus using the method are described herein. The method uses a decision metric for selection that includes a received signal quality metric that takes into account frequency selective fading and colored interference. The decision metric estimates the average error vector magnitude (EVM) relative to the symbol vector magnitude (SVM) and uses the better metric for antenna selection. This relative measure is called relative EVM (REVM). Although the implementation presented here is specific to the OFDM variant of the 802.11 standard, the invention is applicable to receivers that are not necessarily compliant with the OFDM variant of the 802.11 standard.

[0037] One embodiment of the present invention is applicable to communications using OFDM packets that comply with the OFDM variant of the IEEE 802.11 standard. FIG. 6 shows the structure of OFDM packets used in IEEE 802.11a WLAN. The packet begins with a preamble 601, which is used ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

Described herein is an apparatus for inclusion in a station of a wireless network, and a method implemented in a station of a wireless network. The method includes wirelessly receiving data via each of a plurality of antennas (703and 705), the data corresponding to a packet of information transmitted from a remote station, sampling the received data corresponding to the received packet to form data samples for each of the antennas, and determining a measure of signal quality from samples of the received data for each of the antennas. The method further includes selecting (1003) one of the plurality of receive antennas as the antenna for receiving from the remote station according to the determined measure of signal quality.

Description

technical field [0001] The present invention relates to wireless networks, in particular to wireless stations comprising more than one receiving antenna, and to a method of selecting a receiving antenna to use based on a measure of signal quality. In one version, the measure of signal quality is a measure of relative error vector magnitude (EVM). Background technique [0002] Wireless networks such as wireless local area networks (WLANs) have recently become popular. A WLAN can be an ad hoc network where any wireless station (STA) can communicate directly with any other STA, or an infrastructure network where one STA acts as an access point (AP). [0003] The description here assumes that the wireless network complies with the IEEE 802.11 standard, and terminology of the IEEE 802.11 standard will be used. In particular, the invention will be described with reference to a variant of the IEEE 802.11 standard that uses Orthogonal Frequency Division Multiplexing (OFDM), where ...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): H04B1/06H04B7/00H04B7/06H04B7/08H04B17/00
CPCH04B7/0608H04B7/0811H04B7/0814H04B7/082H04B17/309
Inventor 丹尼尔·约瑟夫·洛恩斯布雷恩·哈特
Owner CISCO TECH INC
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products