Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

System and method with interference suppression

A technology for interference suppression and interference suppression, which is applied in the field of interference suppression systems for interference signals, and can solve problems such as different estimation vectors

Inactive Publication Date: 2003-09-03
NTT DOCOMO INC
View PDF0 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, in the case of high-speed fading, this conventional system has a problem that the actual signal estimation vector of the data part becomes different from the channel estimation vector of the known series of symbols due to the fading

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
  • System and method with interference suppression
  • System and method with interference suppression
  • System and method with interference suppression

Examples

Experimental program
Comparison scheme
Effect test

no. 1 example

[0057] The following will refer to figure 2 A first embodiment of the present invention will be described in detail. exist figure 2 , the receiver 10 receives as a received signal a series of N time slots, namely slots S, in burst mode and in order of arrival 1 , time slot S 2 ,...,slot S N .

[0058] Such as image 3 As shown, the time slot S 1 , time slot S 2 , ...slot S N have data part respectively, namely data D 1 , data D 2 ,...,data D N , and the known series of symbols used to estimate the propagation channel for each path, namely MA 1 , MA 2 ,…,MA N . figure 2 The receiver 10 within , demodulates the slot S according to the order of arrival, and by demodulating 1 , time slot S 2 , ...slot S N .

[0059] First, the receiver 10 receives and demodulates a series of incoming time slots one by one. The symbol division device 1 of the receiver 10 receives the time slot S N When the nth time slot S in the N time slots N Divided into data parts (data D...

no. 2 example

[0065] A second embodiment of the present invention will be described below. FIG. 4 is a schematic diagram of a system applicable to an IMT (International Mobile Telecommunications)-2000 / CDMA / TDD system. In Figure 4, each time slot S 1 , S 2 , S 3 Both have a total of 2560 chips, including the midamble of the known series symbol part (256 chips) located in the center of the slot, and two data parts sandwiching the midamble of the known series symbol part, namely the data (1) (1104 chips) and data (2) (1104 chips), and a guard period (96 chips) at the right end of the slot.

[0066] Currently, in the CDMA / TDD system, downlink transmission of TTI=3 slots, in which the receiver 10 performs interference suppression reception by using single user detection (hereinafter referred to as SUD) regarded as a reception method. SUD refers to suppressing interference caused by delayed waves by performing channel equalization at a chip level to restore orthogonality of lost user signals,...

no. 3 example

[0076] In the above-mentioned second embodiment, the channel estimation calculator 3 for each symbol in the demodulation slot S 2 can be used to execute Figure 7 The operation exchange shown. The operation exchange will be described below.

[0077] First, obtain the channel estimation vector H of the current time slot (step S701). Next, obtain the channel estimation vector H' of the previous time slot (step S702). Then, a difference vector G between the channel estimation vector H and the channel estimation vector H' is calculated (step S703). For example, to calculate the slot S 2 The channel estimation vector H 2 with slot S 1 The channel estimation vector H 1 The difference vector G between.

[0078] When the magnitude |G| of the calculated difference vector G is greater than the predetermined threshold "g", the channel estimation vector of each symbol is calculated by performing an interpolation on the channel estimation vector H and the channel estimation vector ...

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

To perform interference suppression for a received signal more precisely. Block dividing section divides a data part of a received slot into several blocks. Channel estimator calculates a channel estimate vector for each block and stores it into channel estimate storage device. Channel estimate calculator for each block calculates a channel estimate vector for each block by using a channel estimate vector calculated with a known series symbol part for the (current) slot and a channel estimate vector for a known series symbol part for a previous slot stored in channel estimate storage device. Then, channel equalizer and de-spreader perform a calculation such as a channel equalizing calculation by using a channel estimate vector for each block at each block.

Description

technical field [0001] The present invention relates to an interference suppression system and method, in particular to an interference suppression system and method for suppressing interference signals in mobile communication. Background technique [0002] In mobile communication systems such as CDMA (Code Division Multiple Access) and TDD (Time Division Duplex), an interference suppression reception method for suppressing interference caused by delayed waves or multiple users is implemented for increasing user capacity . The receiver uses the known series of symbols in the received slots to compute a channel estimate vector to estimate the time of arrival due to each chip level in each received slot, or the fading fluctuations in each propagation channel. The resulting changes in the phase and amplitude of the received signal, and by using the channel estimation vector to perform channel equalization calculations to suppress interference caused by delayed waves or multipl...

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): H04B1/707H04B1/7105H04B1/7115H04L25/02
CPCH04L25/0232
Inventor 石井启之石墨隆之
Owner NTT DOCOMO INC
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com