Adaptive pilot frequency inserting method in OFDM system

A pilot insertion and self-adaptation technology, applied in the field of mobile communications, can solve problems such as low efficiency and waste of spectrum resources, and achieve the effect of improving system work efficiency and system spectrum utilization

Inactive Publication Date: 2006-05-17
ZTE CORP
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  • Abstract
  • Description
  • Claims
  • Application Information

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Problems solved by technology

[0011] The technical problem to be solved by the present invention is to provide a method for adaptive pilot insertion in an OFDM system, so as to overcome the shortcomings of serious waste of spectrum resources and low efficiency due to the use of fixed pilot intervals in the prior art

Method used

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  • Adaptive pilot frequency inserting method in OFDM system
  • Adaptive pilot frequency inserting method in OFDM system
  • Adaptive pilot frequency inserting method in OFDM system

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Embodiment Construction

[0039] The method of the present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0040]The self-adaptive strategy of the present invention utilizes the channel parameters estimated by the receiving end. When the channel changes slowly, the pilot interval is increased, and a pilot model with fewer pilots is used; and when the channel changes quickly, the pilot interval is reduced interval, the pilot model with more pilots is adopted. This method can be used in a TDD system. Due to the symmetry of the uplink and downlink channels, the sender can directly use the uplink information to know the characteristics of the downlink channel. Therefore, the sender can decide which pilot interval model to use without a feedback link. Just send the serial number of the pilot pattern to the receiving end; it can also be used in the FDD system (see attached figure 2 ), the receiving end feeds back a required pilot model ser...

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Abstract

A method for inserting adaptive pilot frequency in OFDM system includes using the sending end to adaptively select pilot frequency model with different interval according to channel parameter estimated by receiving end; increasing pilot frequency interval and applying pilot frequency model lowering pilot frequency quantity when channel is changed at low speed; reducing pilot frequency interval and applying pilot frequency model increasing pilot frequency quantity when channel is changed at high speed; dividing channel parameters, maximum delay expansion and relative Doppler frequency shift to be sections and using different pilot frequency interval to correspond to different pilot frequency model.

Description

technical field [0001] The invention relates to the field of mobile communication, in particular to a method for adaptive pilot insertion in an OFDM (Orthogonal Frequency Division Multiplexing, Orthogonal Frequency Division Multiplexing) system. Background technique [0002] Due to the rapid development of digital signal processing technology, OFDM technology, as a high-speed transmission technology that can effectively resist Intersymbol Interference (ISI, InterSymbol Interference), has attracted more and more attention. OFDM technology converts high-speed data streams through serial-to-parallel conversion, so that the duration of data symbols on subcarriers is lengthened, and ISI can be eliminated by inserting cyclic prefixes. In the OFDM system, each subcarrier is orthogonal to each other, allowing the frequency spectrum of the subchannel to overlap with each other, so that the spectrum resources can be used to the maximum extent. At present, OFDM technology has been suc...

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Application Information

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Patent Type & Authority Applications(China)
IPC IPC(8): H04L27/26H04J11/00
Inventor 单淑伟殷志明
Owner ZTE CORP
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