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OFDM

40407

OFDM

(OFDM)OFDM

OFDM OFDMOFDM

OFDMOFDMOFDMmatlab

OFDM

Analysis and Simulation on OFDM

Synchronization Technology

Author: Guo Haifeng

Tutor: Huang Liqun

Abstract

Orthogonal Frequency Division Multiplexing is one of key technologies in mobile communication fields; it is suitable for high rate data transmission in wireless channels because it can combat Inter-Symbol Interference and multi-path fading efficiently, now it has become an attractive technology. OFDM is a multiple carriers technology, supports high rate data transmission with high spectrum efficiency. At present, OFDM technology has been used in many fields, such as wireless local network, digital audio broadcasting, and digital video broadcasting systems and so on. It is very promising to be a core technology of the fourth generation mobile communications.

At first, the principle, properties and key technology are described simplyseveral synchronization in need for the system are introduced. The effect of synchronization error of an OFDM system is discussed in detail. The study show that symbol timing offset and sampling frequency offset would introduce inter-symbol interference, frequency offset of carriers would result in inter-carrier interference. So, in an OFDM system, finding the symbol timing, the carrier frequency offset, and the sampling rate offset at the receiver is important in the recovery of the signal.

Finally this paper on OFDM system for the simulation, designed OFDM system simulation model developed OFDM system matlab procedures, the various periods of signal transmission waveform were analyzed, and by changing the channel signal to noise ratio of the system against multi-path The ability of the decline.

Key Words: Orthogonal Frequency Division Multiplexing, Carrier frequency offset, Timing error

11

11.1 OFDM

21.2 OFDM

31.3

52 OFDM

52.1 OFDM

62.1.1 0FDM

72.1.2

82.1.3

112.2 OFDM

133 OFDM

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133.1.2 OFDM

153.2 OFDM

163.2.1

173.2.2

203.2.3

263.3

284 OFDM

284.1 OFDM

284.1.1

284.1.2 QPSK

304.1.3

304.1.4 FFT/IFFT

304.1.5//

304.2

354.3

38

39

40

41

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