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### Practicality of the assumption of i.i.d. for Rayleigh channels

I would like to understand how far the assumption of having i.i.d. is accurate/valid (from the practical point of view) when an OFDM system is working in Rayleigh channels. Is this means the channel ...
371 views

### Intersymbol interference due to limited channel bandwidth

What is the difference between limited-bandwidth induced intersymbol interference (ISI) and ISI due to multipath propagation. I noticed that the delay spread in indoor environment is in the range of ...
642 views

### Flat fading criterion of OFDM subcarrier spacing

I have always thought that the OFDM subcarrier spacing $\Delta f$ is chosen such that not too small because Doppler spread can destroy subcarrier orthogonality not too large to avoid Cyclic Prefix (...
429 views

### Educational purpose - What is the correct way to simulate a multipath fading channel which has ISI

I am following the codes for rayleigh fading channel given in the webpage: http://www.raymaps.com/index.php/m-qam-bit-error-rate-in-rayleigh-fading/ I am confused and need help in clarifying some ...
1k views

### Matlab: Difference between flat fading and Rayleigh multipath fading, terminologies and concept

The information that I put down are from the site http://www.gaussianwaves.com/2011/05/ebn0-vs-ber-for-bpsk-over-rayleigh-channel-and-awgn-channel-2/ . My QUestions are due to some misconception and ...
189 views

### Channel capacity with additive Gaussian noise with changing variance

As we all know the capacity for a AWGN channel with constant noise variance is just given by $$\frac{1}{2}\log(1+SNR)$$ What if the variance of the noise changes with the type (assuming the variance ...
50 views

### Actual measurements of the influence of fading and multipath on HF radio communication

I'm looking for papers or books that contain actual measurements of the influence one has to expect in HF radio communication. I'm interested in this, because i've simulated the influence of a ...
54 views

### Transmitting over Unknown Fading Channel

I have a system with no diversity and the channel's coefficients change every $T = 10\text{ bits}$ transmitted. The channel estimation system has a flaw and detects the channel's coefficients equal to ...
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### FWGN model implementation vs explaination (textbook pages attached)

I came across the FWGN model for multipath channel simulation in the book: "MIMO-OFDM Wireless Comuunications with MATLAB" Here is an explanation about Clarke/Gans model: Some code to generate a ...
37 views

It is known that the CDF of the product of two exponential random variables is given by this answer If $X$ and $Y$ have rate parameters $\mu$ and $\lambda$, so their pdf's are $f_X(x) = \mu e^{-\... 0answers 91 views ### How to model fading channels in MATLAB? I am asked to write a MATLAB program for the simulation of the end-to-end transmission of a JPG file through a fading channel by using OFDM technique for one of my courses' term project. I wrote my ... 0answers 89 views ### Ideal channel in OFDM simulation I am trying to simulate an OFDM based system in MATLAB where the estimated channel in the reciever is fed back to transmitter. As a proof of concept I wanted to return the ideal channel. I used the ... 1answer 1k views ### AWGN and Rayleigh fading in slow flat fading channels in MATLAB I wanted to add Additive White Gaussian Noise (AWGN) and involve effect of slow flat fading on my transmitted signal in Matlab. I created noise with zero mean and variance of one by ... 3answers 203 views ### Channel impulse reponse multipaths I find this image : Does it mean that at 0ns there is one path, 10ns second path, ... and approximately at 130 ns, there is a power path? 2answers 371 views ### what does mean quasi-static channel [closed] When I read papers about channels, I usually see something Quasi-static Channel, Does "Quasi-static Channel" mean "time-variant channel" or "time-invariant channel"? 1answer 592 views ### Rayleigh Fading Simulation I have a question about simulating Rayleigh Fading channel. I know theory behind the Rayleigh channel and it is sum of two Gaussian random variable where the amplitude is Rayleigh distributed and the ... 1answer 282 views ### How can I generate time-variant Rayleigh channel in MATLAB One of known models for channel simulation is called Rayleigh Fading channel, it's usually used to simulate wireless channel in time variant/invariant. As I know, Rayleigh fading channel can be ... 1answer 46 views ### Is the Channel shortening similar to Time domain Equalizer (TEQ) I used to read about Time domain equalizer (TEQ) in many lectures, i.e here , But in many other papers, that's called Channel shortening i.e here . However, in the a two above links, the cost ... 2answers 30 views ### Which channel coding technique is suitable for wireless SPIHT compressed image: Reed-Solomon or convolutional code? I want to transmit a SPIHT-based (Set Partitioning In Hierarchical Trees) image compressed image over a wireless fading channel, which will be suitable as channel coding technique: Reed-Solomon or ... 1answer 156 views ### why did convolution coding achieve BER less than Reed-Solomon? I tried convolutional coding and Reed-Solomon (RS) (block coding technique) for wireless channel where the input data is bitstream. Convolutional coding achieved lower BER comparing with RS. If the ... 1answer 144 views ### MIMO System Model in Matlab I have this lame doubt which has ended up confusing me which is probably trivial. I am modelling a MU-MIMO system with a Rayleigh fading channel. I have created a wanted signal as an OFDM signal, and ... 2answers 7k views ### Matlab: Correct method of generating Rayleigh fading channel A Rayleigh flat fading channel has 1 tap and so there will be no intersymbol interference. if N= 1000; Then, h=(1/sqrt(2))*(randn(N,1)+1i*randn(N,1)); will ... 1answer 29 views ### Assessing relative wireless channel quality using Capacity and Condition Number CDFs I have Channel capacity analysis figures for two wireless channels show below: My question: While ergodic capacity in the first subplots are very clear in conveying the channel capacity, How to make ... 2answers 98 views ### BER of QPSK modulation in Rayleigh fading channel model i am having trouble deriving a BER analytical expression for QPSK modulation system operating in a Rayleigh Fading channel model. Could anyone direct me to a reference that would help in this matter. ... 1answer 80 views ### Channel model: LOS Component and Rician K-factor I am asking about Rician K- Factor in this model: I know that if$K=0$then it is a pure Rayleigh fading, if$K= \infty$, then non fading Channel. What is it, if$0<K<\infty$? If i represet ... 2answers 510 views ### How to compute the channel gain from the path loss model of a wireless channel I did my research but I did not get a satisfying answer. We have a transmitter and a receiver over a wireless communication channel. The channel's path loss is modeled as$ 128 + 37 \log_{10} (d)$, ... 1answer 36 views ### Need information about following channel model The following research paper is for blind channel equalization and the author has modeled the channel as 7 tap weights https://ieeexplore.ieee.org/document/1096877 On page 3 it has shown the ... 1answer 73 views ### What's the difference between SISO and SIMO in using matched Filters Suppose we are transmitting a signal$x$in$OFDM$with$N$subcarriers, After performing Parallel/Serial conversion and then N-points FFT, we suppose to have signal$s = IFFT^Hx$, Then adding the ... 1answer 56 views ### When to use Rician fading vs Gain for Directional Antenna This is a pretty simple question. [The answer might not be simple :( ] If I am using a directional antenna, can I used Antenna gain$G_T=1\$ as I am considering Rician Fading between transmitter and ...
480 views

I Read in one reference that, the Rayleigh distribution is commonly used to describe the statistical time varying nature of the received envelope of a flat fading signal, or the envelope of an ...
161 views

### How to get a Rician fading channel matrix from a Rayleigh fading channel matrix?

I have a Rayleigh fading channel matrix H. Let's say the dimension is 2000*128. Is there any way to convert this matrix into a Rician fading channel matrix for example κ = 5, 10, 15, etc.? Is there a ...
120 views

### Demodulation in Rayleigh Flat Fading Channels

A core part of demodulation in Flat-Fading channels is (assuming) the channel as a(random) constant complex number multiplied with your signal. This is done in order to de-rotate the symbol for ...
397 views

### What is the suitable mathematical form of the multipath channel impulse response?

I am trying to understand the nature of a wireless multipath channel impulse response but I am a bit confused while interpreting the time domain multipath impulse response. There are different ...
442 views

### Zigbee Transceiver Using OQPSK Modulation under Fading Channels

I am working on transmitting ECG signal over wireless body area networks. According to IEEE802.15.4 standards , I am using ZigBee transceiver at 2.4 GHZ . Complex baseband equivalent channel model is ...
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### Brief introduction to wireless communication and communication terminologies [closed]

In the Question Design of equalizer for wireless communication the diagram of a basic communication system is presented with informative points and discussions. My Questions are: Considering the ...
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### Help in analytical expression of BER for M-QAM [duplicate]

I am new in learning deriving BER expression. I am familiar for the case of BPSK in AWGN but cannot understand how the BER expression in Eq(12) in this paper, An Enhanced Spectral Efficiency Chaos-...
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### Conceptual Question on equalization technique in rayleigh fading channel based on a paper

Question Link http://www.raymaps.com/index.php/theoretical-ber-of-m-qam-in-rayleigh-fading/ gives theoretical expressions for BER in Rayleigh fading channel. Can I use the expression for 64-QAM in ...
543 views

### Matlab: Help in applying equalizer and proper calculation of symbol error rate for QAM modulation in Rayleigh channel

I am unable to understand why the Constant Modulus ALgorithm is not functioning properly for QAM modulation in Rayleigh multipath fading. The same code worked for BPSK in AWGN (previous Question ...
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### channel gain calculation

I want to calculate the SINR term in an up-link of wireless communication system but there is different models for simulation. I want to know what is the exact meaning of |h|^2 in this formula: SINR = ...