Questions tagged [mimo]
The mimo tag has no usage guidance.
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About generating MIMO FMCW IF Signal and angle detection
I want to detect some targets where their range, velocity and angle information can be given before creating the radar cube. Then using IF signal for MIMO FMCW radar I want to construct the radar cube....
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compute EVM for MIMO channel including additive Gaussian white noise
Good time. I would like to compute EVM for a Rayleigh channel including additive Gaussian white noise. The accepted EVM for BPSK issued by IEEE is -5dB. Since the variance of white noise depends on ...
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What is the pdf of the received signal in MIMO radar for CRLB?
I studied a conference paper, High Resolution Capabilities of MIMO Radar and confused about its formula (3).
As mentioned in paper that the noise $n_{k,l}(t)$ in the received signal $r_{k,l}(t)$ ($r_{...
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What is the difference between array gain and diversity gain?
In a multi-antenna system, we often mention diversity gain in fading channels. I am doing simulations with multiple antenna settings at the receiver considering TDLC channel, for example, 1rx, 2rx, ...
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MIMO LMMSE detector: why 8x8's BER is better than 4x4?
I am simulating the MIMO linear detector algorithms including Matched Filter, Zero Forcing and Linear MMSE.
I simulated three configures: 4x4 ( 4 tx antennas 4 rx antennas ), 8x8 and 16x16.
For ...
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How can I compute virtual array via convolution?
I am starting to learn MIMO transceivers and I would like to compute the virtual array of my configuration. To do so, I am following these set of equations 2 and 3, to achieve (3) I was trying to use ...
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Understanding Maximum likelihood detector expression?
Consider the MIMO system which has $N_t$ antennas at transmitter and $N_r$ antennas at receiver and uses Generalized space shift keying (GSSK) modulation. The received signal is given by:
$$Y = H X + ...
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Is it possible to generate SAR like pictures with a non moving MIMO radar and static scene?
Recently I study radar alot and was wondering if there is a possibility to generate SAR like pictures with MIMO radar.
Under the condition that the MIMO radar is not moving and the scene does not ...
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Diversity gain in MIMO-OFDM system
What is the diversity gain in $4\times2$ vs $2 \times 2$ MIMO system. Is it $10 \log \left( N_{t} - N_{r} \right)$?
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If the signal and the noise term separately are coloured, can the resultant signal + noise be white? If yes, how is it good for signal detection?
Let's say we have a received signal at each antenna of a $n_r\times n_t$ MIMO system -
$$r = L_rGs + w$$
where $G$ is the channel matrix consisting of MIMO channel coefficients that are i.i.d., $L_r$ ...
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MIMO antennas and Resource Block
Assuming there are 4 transmit antennas, do these four antennas share the bandwidth?
In other words, I wonder if these four antennas use one resource grid.
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What does QCL quasi-colocation actually mean?
Quasi-colocation is a concept stated in 5G NR specifications. But I'm not quite sure about what it actually means. Is one of its meanings that the propagation channel of the physical channel has the ...
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How to estimate Range, Doppler and Angle with FMCW MIMO Radar?
I am trying to obtain the range, Doppler and angle of arrival estimation with an TDM MIMO FMCW radar.
Actually, I have completed this process. In doing so, however, a few things remained unclear. ...
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How to decode a MIMO stream using V-BLAST?
I am attempting to implement the V-BLAST algorithm for MIMO streams as described by Wolniansky et al. in the following paper: https://ieeexplore.ieee.org/document/738086 (I am not commenting on its ...
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Why the transpose of wireless channel vector is taken in SIMO system?
I am getting confused about the received signal expression in case of SIMO wireless channel.
SIMO system=> Here we will have one antenna at Tx and multiple ($N$) antenna at Rx.
Therefore received ...
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Pdf of product of two i.i.d random variable distributed as circular symmetric gaussian
What is a distribution of the product of two circular symmetric Gaussian random variables?
i.e $X ~ CN(0,1)$ and $Y ~ CN(0,1)$ then distribution of $XY.$?
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MIMO detection using ZF and MMSE
I have a problem related to my uni assignment. The task seems rather simple - plot SER as a function of Es/N0 for 2x2 MIMO and 16-QAM modulation assuming AWGN noise and Rayleigh flat-fading channel. ...
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High frequency and received signal power? Why using massive MiMo?
The power received by an isotrapic antenna is calculated by:
$P_0=\frac{P_T}{4 \pi d^2}\cdot \frac{\lambda^2}{4 \pi} = \frac{P_T}{4 \pi d^2}\cdot A_e$
or, by Friis transmission formula:
$\frac{P_r}{...
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Complexity of ZF precoding at the transmitter
If we have a modulated signal $s$ and ($m\times n$) MIMO channel $H$ where $m$ and $n$ are number of receive and transmit antenna, respectively. The ZF pre-coded signal is
\begin{equation}
x=Fs
\end{...
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How to build a model for $2 \times 2$ MIMO using GNU Radio?
I have been trying to set up a GNU Radio flowgraph where I can implement a $2 \times 2$ MIMO system. don't know how to make spatial diversity using the blocks, also I am not sure which block ...
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121
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Square Root MMSE
Could anyone please explain how to perform the derivation of the square-root MMSE equation using an extended channel matrix H (as it is said in the "A LOW COMPLEXITY SQUARE ROOT MMSE MIMO DECODER&...
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Radar MIMO Virtual Antenna Array Formation
Referring to the figure attached above, is the ordering of the virtual antenna arrays (shown on the right) to measure azimuth and elevation angles of arrival correct? In my understanding, the ordering ...
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How to calculate received signal power for a Multi-User MIMO OFDM system?
I have a Multi-User MIMO system where there are 2 users served by a base station. The base station consists of 64 transmit elements and the users are equipped with linear antenna array consisting of 3 ...
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Can beamforming be created by transmitting same signal with different phase
As known, the basic idea of beamforming is to transmit the same signal using more transmit antennas, let's say we have $4$ transmit; leading to increase the power of the transmitted signal as well as ...
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52
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Alamouti scheme and MIMO OFDM model, theoretical or practical concept?
I am not an expert in signal processing but last week I attended a class of signal processing. We discussed MIMO, OFDM and Alamouti scheme.
On this lecture it was represented a lot of math equations, ...
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Matlab: Could anyone suggest why Iam getting a different geometry for QPSK constellation diagram
I'm developing a Multi-user MIMO communication model in MATLAB where a base station communicates with 2 users. The model uses OFDM (QPSK) modulation. Channel model, precoding and covolutional encoder ...
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Does same data inserted to all antenna at beamforming?
I wonder do I understand beamforming right.
Question 1
Does same data inserted to all antenna at beamforming? Like figure below? The only different is through different phase shift? If it is right how ...
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Property of the trace and expectation
I'm reading the paper Model-Driven Deep Learning for Joint MIMO Channel Estimation and Signal Detection by Hengtao He, Chao-Kai Wen, Shi Jin, and Geoffrey Ye Li on Orthogonal Approximate Message ...
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Blind STBC question
I am working on blind identification of the physical layer parameters of a particular protocol. Everything was going well until I got to the MIMO part. The system contains two transmitter antennas and ...
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What is the Co-channel interference in MIMO communication
I try to understand the co-channel interference occurred in MIMO systems with rich multi-path channels, but I couldn't find clear explanation about how it happens and what's its effects to the ...
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Inter Channels interference in MIMO system
If we have MIMO system with $2$ transmit antennas, ($T_1$ and $T_2$) and $2$ receive antennas ($R_1$ and $R_2$). The received signal of the first received antennas can be explained:
$r_1$ = $h_{11}$$...
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FMCW Radar - Range-Doppler Plot
The FMCW radar with the following parameters was implemented:
...
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Radar for Vital Signs – Matlab Simulation
Interested to design and simulate FMCW radar for Vital Signs sensing.
The initial signal parameters are(1):
When using the following Matlab code to generate the waveform:
...
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Spatial multiplexing MIMO, antenna critical spacing, antenna isolation
How does antenna isolation affect single user spatial multiplexing MIMO performance in an antenna array? Text books talk about a critical antenna spacing of 1/2 of the wavelength provided that the ...
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Multi-input Single-output communication system
In case of communication in MISO system, if we have a system of 4 x 1, which means 4 transmitter with 1 receiver. Will the received signal be a vector of dimension 4 x 1 ? Or it will be 1 x 1 since ...
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how to determine a length of a channel? ( given path, delay)
Given a channel matrices for each subcarrier of a frequency selective channel (OFDM): i.i.d..
channel =(randn(ntx,nrx, N)+1i*randn(ntx,nrx, N))/sqrt(2); simulated ...
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Control of a nonlinear static MIMO System
I am currently writing my master thesis and trying to design a controller for my system. However, the system is somewhat unconventional.
It has a large number of inputs and outputs, is static, non-...
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What is the difference between ISI and MAI in MIMO system?
ISI ： inter-symbol interference
MAI ： Multiple Access Interference
I know that multi-path would caused delay spread, and when signal symbol period is less than delay spreaad, ISI would happened.
...
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What is the physical meaning of coherence bandwidth in mmWave massive MIMO channel?
I am doing some research about millimeter wave massive MIMO channel now.
We first take account about static MIMO channel, cause we only have SISO measurement system now.
We use scanner to move our ...
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95
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Subcarrier assignment in MIMO-OFDMA system
Is it possible for multiple users to simultaneously transmit on the same subcarrier in a MIMO-OFDMA system?
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MIMO multipath delay [duplicate]
How is multi-path delay dealt with in MIMO systems? Most of the theory I have read on MIMO doesn't address multipath delay and assumes the multipath interference is limited to secondary antenna ...
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How to understand MIMO zero forcing as a bank of decorrelators?
I am studying the zero forcing as a simple linear receiver for MIMO detection. according to these notes.
The zero forcing can be understood as the following two ways.
For a single stream $\mathbf{q}$,...
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LTE system. How to compute precoder for resourse block
guys!
I am studying a massive Mimo system and 3gpp LTE system and have questions about precoding in the LTE system. In LTE RB (resource block) is used to group consecutive subcarriers. To compute ...
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130
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Pairwise Error Probability simulation versus SNR for Space-time code
I have a MIMO system using Space-time coding. I am required to produce simulation results in the form $\text{PEP}=f(\text{SNR})$, meaning a curve representing the Pairwise Error Probability (PEP) for ...
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Achievable rate for MIMO channel with estimated channel matrix
In a MIMO system, if the receiver has perfect CSI, i.e. knows that channel matrix $\boldsymbol{H}$, then the achievable rate is:
$$ R = \log \left|\boldsymbol{I}+\frac{P}{N_RN_T}\boldsymbol{H}\...
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Space-Time coding uses large amount of block codes to acheive maximum spectral efficiency
Assume I have a MIMO system with $M=8$ transmit antennas, and an arbitrary number of receive antennas.
This MIMO systems uses space-time coding. the block codes (matrices) transmitted are part of a ...
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Notes or books to quickly get started on the basics of signal processing or wireless communication
I'll soon start working in signal processing, specially wireless communication systems. Hence I'd like to get a quick understanding of MIMO and related systems, for example, the topics like:
1) where ...
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Range Migration Algorithm in FMCW MIMO RADAR
I’m using a FMCW MIMO radar [77-79 GHz] with a virtual linear array made of 48 channels.
I’m wondering if the adaptation of the range migration algorithm (typically used in SAR processing) is ...
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Why can we know the best precoding direction after we do the SVD to the channel?
Why can we know the best precoding direction after we do the SVD to the channel?for example
$\mathbf y=\mathbf H\mathbf s+\mathbf n$,now we do the SVD to the $\mathbf H$
If the $\sigma _1$ is the ...
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Frequency-selective channel: Basic in theory
In a lecture, it was covered a topic "frequency selective and flat fading channel models".
For case, the frequency selective channel we have a channel impulse response ...
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