SPECTRAL EFFICIENCY:
Spectrum efficiency is the optimized use of spectrum. so that the maximum amount of data can be transmitted with the fewest transmission errors. In a Cellular telephone network, spectrum efficiency equates to the maximum number of users per cell that can be provided while maintaining an acceptable quality of service (OFDM) is the method of choice for combating frequency-selective multi path fading channels, and achieving high spectral efficiency in wireless communication systems. With the aid of sufficient cyclic prefix, inter-symbol interference (ISI) due to multi path fading is completely avoided without the need for complicated equalizers.
Fig: OFDM
However, despite the fact that CFO estimation and compensation is performed at the receiver, a random residual CFO still exists which increases at low number of training symbols and/or low to medium signal to noise ratio (SNR) region. Further, this residual CFO might degrade the OFDM system performance.
Even though CFO estimation is performed at the receiver, a residual frequency offset still exists and introduces ICI which degrades the OFDM system performance over multipath wireless channels.
In addition, low fixed pilot power results in a spectral efficiency ceiling as SNR increases, whereas in the equal pilot and signal powers case, spectral efficiency increases with SNR without bound
FOR MORE DETAILS:
Spectrum efficiency is the optimized use of spectrum. so that the maximum amount of data can be transmitted with the fewest transmission errors. In a Cellular telephone network, spectrum efficiency equates to the maximum number of users per cell that can be provided while maintaining an acceptable quality of service (OFDM) is the method of choice for combating frequency-selective multi path fading channels, and achieving high spectral efficiency in wireless communication systems. With the aid of sufficient cyclic prefix, inter-symbol interference (ISI) due to multi path fading is completely avoided without the need for complicated equalizers.
However, despite the fact that CFO estimation and compensation is performed at the receiver, a random residual CFO still exists which increases at low number of training symbols and/or low to medium signal to noise ratio (SNR) region. Further, this residual CFO might degrade the OFDM system performance.
Even though CFO estimation is performed at the receiver, a residual frequency offset still exists and introduces ICI which degrades the OFDM system performance over multipath wireless channels.
In addition, low fixed pilot power results in a spectral efficiency ceiling as SNR increases, whereas in the equal pilot and signal powers case, spectral efficiency increases with SNR without bound
FOR MORE DETAILS:
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