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### HF ionospheric Channel Model Example in matlab : Watterson model

In the example file in matlab HFIonosphericChannelModelExample.m, the watterson model is simulated. In this model the channel is represented as one tap (for the sake of simplification) delay channel. ...
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### How to choose the algorithm for DFE filter adapatation, if the criterion is MMSE?

I hesitate between LMS and RLS , and for the feedforward filter and feedback filter, what must be the length of the filters as a function of the channel delay spread. Any help will be really ...
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### Hf ionospheric channel model for large bandwidth

I know some models like the Watterson model for HF ionospheric channels but those are limited to narrow band frequencies. Are there some models to bandwidth like 12kHz up to 24 kHz?
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### Detect orthogonal sequence with fading

For a set of $N$ orthogonal sequences $\textbf{A}^i = \{a_1^i,a_2^i,...,a_M^i\}, i =1 ..N$, the detection of these sequences can be done by calculating the inner product (dot product) of receive ...
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### How to determine a number of taps in channel

I need to determine the number of taps of a channel. I have the channel simulated via channel simulator. My task is to try to estimate the channel by using pilots position. How the channel was ...
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### Is MMSE equalizer necessary?

For observation $y$, channel coefficient $h$ and gaussian noise $w \sim \mathcal{CN}(0,\sigma^2)$, $$y = hx + w \tag{1}$$ Note that for OFDM system, (1) is assumed channel input-ouput equation on ...
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### Path delay influence in BER performance using Rayleigh channel

I am simulating a DSSS modulation in a Rayleigh channel to get the BER performance. For these purpose I am using the comm.RayleighChannel object. My problem comes when I change the Paths delays of the ...
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### Basic in frequency-selective channel: part with decoding

Here I have asked about the basic of the theory of frequency selective channel and the user @Florian explained to me how to compute precoding in such case using the effective channel. I am just ...
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### Wireless Channel Modelling - LOS

Let $T$ a transmitter and $R$ a receiver in a wireless scenario. The two entities are in an outside scenario with Line of Sight. The transmitter $T$ sets its maximum power transmission $P_{TX}$ and ...
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### Relation between PDP (Power Delay Profile) and channel impulse response

I am traying to perform a simulation in Matlab and I faced up with some practical/theorical problems. The channel I want to simulate is frequency selective fading. The packets are short compared with ...
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### Meaning: channel unknown and known at the transmiiter

What does "channel unknown" and "known at the transmitter" mean? In books about signal processing, it has always mentioned it if capacity or transmission (estimation) is discussed. I can't understand ...
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### Time variant frecuency selective fading in matlab

I am traying to simulate a frequency selective fading channel in Matlab and I have faced with some issue/questions during the implementation. It is a DSSS (BPSK) modulation and the code is organized ...
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### How to estimate the channel in DS CDMA system

I am working with DS-CDMA system based on multi-path Rayleigh channel,My question, how can I estimate the channel from the received signal to cancel the effect of channel? for example in OFDM system ...
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### How to generate rayleigh fading coefficients in matlab

I want to calculate received SNR for each cellular user CUs, so i want the corresponding transmission power P of base station BS to each user, the noise, and the channel gain coefficient of the ...
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### I don't know why the packet size is considered in this packet reception probability equation

https://www3.nd.edu/~mhaenggi/pubs/broadnets04.pdf In 3 page of this paper, the packet reception probability without interference is $e^{-\theta N Ad^2/ P}$. $\theta$ is sinr threshold. $N$ is a ...
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### Why are the following two packet reception probabilities different?

https://www3.nd.edu/~mhaenggi/pubs/broadnets04.pdf In 3 page of this paper, the packet reception probability without interference is $e^{-\theta N Ad^2/ P}$. $\theta$ is sinr threshold. $N$ is a ...
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I want to cross-fade from one signal smoothly to another signal. Example: Signal1 = 5 Signal2 = 1 I already looked for algorithms/ procedures but could not find anything helpful. As I am not that ...
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### Detecting multi-path propagation when one acoustic signal is dominant

I am sending an acoustic signal from a source to a receiver where there are limited number of paths the signal can travel. I want to detect if there has been multipath propagation or not when one path ...
33 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 ...
115 views

### SNR and Correlation

Signal to Noise ratio is essentially the ratio of the signal power to the average noise power. Correlation is the similarity of two signals. Assuming a signal travels through a channel or medium, and ...
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### Channel information from power spectra

Linked below is a previous post regarding a multipath channel. Equalisation of FFT spectra I am reusing the images here: The first image is that of the power spectra when there is no multipath and ...
72 views

### Validating Jakes model in Rayleigh Fading channels

I am trying to validate the Jakes model by comparing the autocorrelation function given by $\rho(\Delta t ) = J_{0}(2 \pi f_{d} \Delta t)$, where $f_{d}$ is the maximum Doppler shift, $J_{0}$ is ...
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I am looking to simulate a radar channel and a waveform to test some ideas from other signal processing domains on automotive radar. However, I have no experience with the typical automotive radar ...
36 views

### What's the effect of spread spectrum on frequency- selective channel

In brief, we consider the channel as frequency-selective channel if the frequency of the signal is larger than then frequency of channel. So, does using the spreading spectrum change the frequency-...
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### Explanation a flat fading channel in case MIMO OFDM

I am trying to understand flat fading and frequency selective channels. As I understood, in the case of flat fading channels MIMO channel elements, $h_{i,j}$, are random variables. Which assumption ...
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### Frequency selective channel modeling using rayleighchan object in matlab

I intend to model a frequency selective channel using matlab "comm.RayleighChannel" object. Consider the following command, which sets the parameters of Rayleigh channel : ...
313 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. ...
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### Channel models for wireless body area networks

To transmit a signal over wireless body area network, the signal is transmitted over a fading channel with additive white Gaussian noise. The channel model can be obtained from the IEEE standards. My ...
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### 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 ...
55 views

### Channel estimation

In single-carrier systems, at the receiver, when we need to do channel estimation and equalization? Do we need to do before timing synchronization and CFO correction or before it? And, please let me ...
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### Designing Rayleigh Fading Wireless Channel with particular properties [closed]

I have some information on particular wireless channel between an Access Point(AP) and K users as described in the picture below: How i can create this channel in Matlab?
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