Unlock instant, AI-driven research and patent intelligence for your innovation.

Signal emitting and receiving method based on orthogonal frequency division multiplexing (OFDM) frequency spectrum compression

A technology of signal transmission and reception methods, applied in multi-frequency code systems and other directions, can solve problems such as inability to guarantee user access, improve spectrum utilization and time utilization, reduce bandwidth and time slot requirements, spectrum and time slots the effect of compression

Active Publication Date: 2015-03-11
HARBIN INST OF TECH
View PDF2 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, with the increase of cell users, especially in hotspot areas, and the upgrading of users' demand for communication data rates, the increasingly tight spectrum and time domain resources will not be able to guarantee the access of all users

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
  • Signal emitting and receiving method based on orthogonal frequency division multiplexing (OFDM) frequency spectrum compression
  • Signal emitting and receiving method based on orthogonal frequency division multiplexing (OFDM) frequency spectrum compression
  • Signal emitting and receiving method based on orthogonal frequency division multiplexing (OFDM) frequency spectrum compression

Examples

Experimental program
Comparison scheme
Effect test

specific Embodiment approach 1

[0024] Specific implementation mode 1. Combination Figure 1 to Figure 3 Describe this specific embodiment, the signal transmission and reception method based on OFDM spectrum compression,

[0025] Signal transmission method:

[0026] Step A1. Premodulate both the real part sequence Re{s} and the imaginary part sequence Im{s} of the data source sequence s using FFT and IFFT to obtain the real part premodulation sequence Re{X} and The imaginary part premodulates the sequence Im{X}; at the same time, the real part suffix sequence Re{ the s (1)} and the imaginary suffix sequence Im{s (1)};

[0027] Among them, the real part of the intractable point satisfies: Re{s n}=-Re{s N-n}’s real part point; similarly, the imaginary part’s intractable point satisfies: Im{s n}=Im{s N-n}'s imaginary part.

[0028] Step A2, the real part premodulation sequence Re{X} and the imaginary part premodulation sequence Im{X} of the data source sequence s obtained in step A1 are respectively int...

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

The invention relates to the field of wireless communication, discloses a signal emitting and receiving method based on orthogonal frequency division multiplexing (OFDM) frequency spectrum compression and provides a new data transmission scheme in an OFDM system. Data symbols are subjected to premodulation at a transmitting end so that the length of a transmitting data block is reduced, and OFDM symbol occupied bandwidth is compressed; and the block which is subjected to frequency spectra compression is subjected to the same post-demodulation at a receiving end, and data at the transmitting end are recovered according to constellation messages. The premodulation and the post-demodulation of the data symbols are achieved through fast Fourier transform (FFT) and inverse fast Fourier transform (IFFT), source data symbol sequences are converted to sequences, the front half section and the rear half section of the sequences are in a conjugate symmetry relation, and the transmitted symbols are further compressed. The method achieves compression of OFDM frequency spectra and time slots and is applicable to wireless communication.

Description

technical field [0001] The invention relates to the field of wireless communication, in particular to a transmission method for saving time-frequency domain resources under the OFDM system. Background technique [0002] With the increase of communication data rate, the shortage of spectrum resources caused by the increase of communication signal bandwidth is becoming more and more serious. The communication system adopts a frequency division access method based on OFDM (Orthogonal frequency division multiplexing) technology to realize the downlink communication of the cellular network cell. OFDM saves spectrum resources by multiplexing orthogonal subcarriers. However, with the increase of cell users, especially in hotspot areas, and the escalation of users' demand for communication data rates, the increasingly tight spectrum and time domain resources will not be able to guarantee the access of all users. Therefore, how to reduce the demand for bandwidth and time slot is an...

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 Patents(China)
IPC IPC(8): H04L27/26
Inventor 沙学军王焜李勇房宵杰吴宣利梅林
Owner HARBIN INST OF TECH