PLC (Power Line Communication) is a data transmission method using the power line as the communication media. The wide coverage, the low cost and the convenient access of powerline network grant itself a unique advantaged technology to access network. But the noises, the frequency selective attenuation and the multi-path propagation inherently existed in the power
(Read More…)
Adaptive modulation technique is an effective solution to the scarcity of spectral efficiency (SE) in mobile communication systems. The key ideas of adaptive modulation technique are as follows:the receiver estimates channel state information (CSI) and sends the estimated CSI back to the sender, then the sender adjusts the modulation mode based on the decision criterion
(Read More…)
Channel state information is required in OFDM systems for correlation detection and in MIMO-OFDM systems for space-time decoding. Meanwhile, it is also the required information to the transmitter in closed-loop systems. Therefore, channel estimation is very important, especially, its accuracy affects the overall performance directly in MIMO-OFDM systems. On the other hand, adaptive modulation technique
(Read More…)
This paper introduces the principle and techniques of the PPM-UWB communication system under the background of the communication of ultra wide band(UWB). It put forward the transmission theory of adaptive PPM modulation(AM). It’s based on the channel estimation, using a feedback channel to send the channel state information (CSI)to transmitter. The CSI is used to
(Read More…)
Channel state information is required in OFDM systems for correlation detection and in MIMO-OFDM systems for space-time decoding. Meanwhile, it is also the required information to the transmitter in closed-loop systems. Therefore, channel estimation is very important, especially, its accuracy affects the overall performance directly in MIMO-OFDM systems. On the other hand, adaptive modulation technique
(Read More…)
Orthogonal Frequency Division Multiplexing(OFDM) as a multi-cartier modulation technology has high bandwidth-efficiency and the ability in coping with multipath fading,which make it suitable for high speed wireless transmission.It’s supposed that OFDM will have an extensive application in wireless communication.Now it has been adopted as the physical-layer technology of several specifications.Also many expects that it will
(Read More…)
Orthogonal Frequency Division Multiplexing(OFDM) as a multi-cartier modulation technology has high bandwidth-efficiency and the ability in coping with multipath fading,which make it suitable for high speed wireless transmission.It’s supposed that OFDM will have an extensive application in wireless communication.Now it has been adopted as the physical-layer technology of several specifications.Also many expects that it will
(Read More…)
This paper introduces the principle and techniques of the PPM-UWB communication system under the background of the communication of ultra wide band(UWB). It put forward the transmission theory of adaptive PPM modulation(AM). It’s based on the channel estimation, using a feedback channel to send the channel state information (CSI)to transmitter. The CSI is used to
(Read More…)
Channel state information is required in OFDM systems for correlation detection and in MIMO-OFDM systems for space-time decoding. Meanwhile, it is also the required information to the transmitter in closed-loop systems. Therefore, channel estimation is very important, especially, its accuracy affects the overall performance directly in MIMO-OFDM systems. On the other hand, adaptive modulation technique
(Read More…)
Orthogonal Frequency Division Multiplexing(OFDM) as a multi-cartier modulation technology has high bandwidth-efficiency and the ability in coping with multipath fading,which make it suitable for high speed wireless transmission.It’s supposed that OFDM will have an extensive application in wireless communication.Now it has been adopted as the physical-layer technology of several specifications.Also many expects that it will
(Read More…)
