What is MMSE in MIMO?
In the con- text of MIMO systems, linear receivers such as the minimum mean square error (MMSE) receiver are adopted in some of the emerging standards, e.g. IEEE 802.11n and 802.16e. Therefore the analysis of MMSE receivers is strongly motivated by both theoretical and practical considerations.
What is MMSE receiver?
Multiple-input multiple-output (MIMO) Minimum mean-square error (MMSE) receivers are widely adopted in the latest communication standards and reducing the complexity of these receivers while preserving the error performance is highly desirable.
What is zero forced receiver?
Zero Forcing Equalizer refers to a form of linear equalization algorithm used in communication systems which applies the inverse of the frequency response of the channel. The name Zero Forcing corresponds to bringing down the intersymbol interference (ISI) to zero in a noise free case.
What is ML detector?
maximum likelihood (ML): This is the optimal detector from the point of view of minimizing the probability of error (assuming equiprobable x). The maximum likelihood detector with IID Gaussian noise at the receiver antennas solves the following problem.
What are the drawbacks of zero forcing algorithm?
Explanation: The zero forcing algorithm has the disadvantage that the inverse filter may excessively amplify noise at frequencies where the folded channel spectrum has high attenuation. 8.
What is regularized zero forcing precoding?
Regularized zero-forcing (RZF) [7] is a linear precoding technique shown to be effective for single-cell communication systems. RZF has also been extensively used in the analysis of 5G technologies such as massive MIMO [8].
What is the principle of ML receiver?
What is it about? The principle of maximum likelihood is a method of obtaining the optimum values of the parameters that define a model. And while doing so, you increase the likelihood of your model reaching the “true” model. Okay.
Which of the following algorithms used in MIMO?
Hence, low computational complexity algorithm achieving near-optimal performance is required; many existing detection algorithms like zero forcing (ZF), minimum mean-square error (MMSE), and successive interference cancelation (SIC) are used to deal with massive MIMO detection.
Is an algorithm for equalizer?
Explanation: Three classic equalizer algorithm are zero forcing (ZF) algorithm, least mean squares (LMS) algorithm and recursive least squares (RLS) algorithm. They offer fundamental insight into algorithm design and operation.
How does equalizer remove ISI?
If the channel response (or channel transfer function) for a particular channel is H(s) then the input signal is multiplied by the reciprocal of it. The zero-forcing equalizer removes all ISI, and is ideal when the channel is noiseless.
Why is precoding done?
Precoding is a generalization of beamforming to support multi-stream (or multi-layer) transmission in multi-antenna wireless communications. When the receiver has multiple antennas, single-stream beamforming cannot simultaneously maximize the signal level at all of the receive antennas.
What is zero forced MIMO?
Zero-forcing (or null-steering) precoding is a method of spatial signal processing by which a multiple antenna transmitter can null the multiuser interference in a multi-user MIMO wireless communication system.
What does MU MIMO stand for in WiFi?
Luckily, there’s a new technology standard in town that drastically reduces wait time, and its name is MU-MIMO. Multi-user, multiple-input, multiple-output technology—better known as MU-MIMO (a.k.a. Next-Gen AC or AC Wave 2)—allows a Wi-Fi router to communicate with multiple devices simultaneously.
How does MIMO communication work in both directions?
MIMO communication works in both directions (i.e. from AP to client device and from client device to AP), but the maximum number of spatial streams between the access point and the client device is always limited by whichever device supports FEWER spatial streams.
What kind of equalizer is used for MIMO?
Describes a 2×2 MIMO system using Minimum Mean Square Error (MMSE) equalizer for BPSK modulation in Rayleigh channel. Matlab/Octave simulation model provided.
What is the purpose of MU-MIMO Wave 2?
MU-MIMO is introduced in 802.11ac wave 2, and is intended to better handle very high density client device environments (e.g. college lecture halls, convention centers, auditoriums, concert venues, etc.).