What is channel estimation in MIMO-OFDM?
The channel estimation is carried out with conventional Least Square (LS) and Minimum Mean Square (MMSE) estimation algorithms. The performance of MIMO-OFDM system is evaluated on the basis of Bit Error Rate (BER) and Mean Square Error (MSE) level.
Does MIMO use OFDM?
It combines multiple-input, multiple-output (MIMO) technology, which multiplies capacity by transmitting different signals over multiple antennas, and orthogonal frequency-division multiplexing (OFDM), which divides a radio channel into a large number of closely spaced subchannels to provide more reliable …
Does OFDM support beamforming?
OFDM communications have been proposed and analyzed. (RLS), are considered as adaptive beamforming algorithms.
What is meant by channel Estimation?
Channel Estimation is the process of finding correlation between the array of complex numbers on the left and the array of complex numbers on the right. The detailed method of the estimation can very depending on the implementation.
What is channel Estimation in wireless communication?
One of vital parts of the mobile wireless channel is channel estimation, which is a method used to significantly improve the performance of the system, especially for 4G and Long Term Evolution (LTE) systems. Channel estimation is done by estimating the time-varying channel frequency response for the OFDM symbols.
How is OFDM typically realized at the transmitter?
The inverse fast Fourier transform can therefore be used to realise the basic OFDM signal at the transmitter and the FFT can be used to recover (de-multiplex) the symbols at the receiver.
What is the difference between MIMO and OFDM?
While OFDMA is ideal for low-bandwidth, small-packet applications such as IoT sensors, MU-MIMO increases capacity and efficiency in high-bandwidth applications like mission-critical voice calls and video streaming.
What are the techniques used in channel estimation?
Channel estimation at pilot frequencies is based on LS and LMS methods while channel interpolation is done using linear interpolation, second order interpolation, low-pass interpolation, spline cubic interpolation, and time domain interpolation.
Why is channel estimation necessary?
Channel estimation plays an important role in a communication receiver. In order to mitigate hostile channel effects on the received signal, precise channel estimation is required to provide information for further processing of the received signal. Channel estimators can be categorized as non-data-aided or data-aided.
How is channel estimation done?
Channel estimation can be carried out in different ways: with or without the help of a parametric model, using frequency and/or time correlation properties in the wireless channel, blind methods or those based on training pilots, adaptive or non-adaptive methods.
What is channel bandwidth?
In 3GPP the channel bandwidth is defined as the occupied bandwidth of a modulated waveform which corresponds to the frequency range containing 99% of the total power of the modulated signal. An LTE-M-U narrowband of 6 PRBs have a 1.4 MHz channel bandwidth according to this definition which is reused by ETSI.