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Summary. OFDM is a bandwidth efficient modulation technique that is tolerant to channel disturbance such as delay spread multipath and impulse noise.
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Summary OFDM is a bandwidth efficient modulation technique that is tolerant to channel disturbance such as delay spread multipath and impulse noise. The principle of OFDM is to split high-rate data-streams into number of lower rate streams that are transmitted simultaneously over a number of sub-carriers. To demodulate the OFDM subcarriers, it has to perform at least two synchronization tasks: symbol timing and frequency synchronization. Frequency offset destroys the orthogonality between tones. It is important to obtain an accurate estimate of carrier frequency in order to minimize degradation. OFDM has a higher PAPR than concentional single carrier systems. These attributes require that special attention be paid to the linearity of power amplifiers, or be taken to decrease the PAPR. 2.5.7
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