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frequency selective channel $\ne$ multi-tap channel?

A frequency selective wireless channel is necessarily a multi-tap channel, in the tap-delay line model, as the delay spread is significantly larger than the symbol duration. And a single-tap channel ...
syeh_106's user avatar
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Free space path loss and Rician fading

Let a be a qam symbols vector , they pass through ofdm modulator by applying ifft and adding cyclic prefix and I apply comm.RicianChannel function for modeling rician fading I want to introduce also ...
ahmed bennani's user avatar
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2 answers
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Understanding about correlation between random variables in context of Wireless Communication

I am trying to understand about correlation between random variables in context of wireless communication. In research papers related to 6G, I came across the following statements: Suppose there is a ...
Tushar Muratkar's user avatar
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Modeling channel for Multiple users using Rayleigh

I am trying to reproduce the results of a given paper using their approach and model. I have a difficult time understanding a statement in the paper and have doubts about how to interpret it. The ...
Mohamed Abuain's user avatar
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Understanding the additive white Gaussian noise (AWGN) representation

In my research work in wireless communication, I came across an equation of received signal wherein the AWGN is denoted by $n\sim\mathcal{C}\mathcal{N}(\textbf{0},\textbf{I}_L)$. Note that dimension ...
Pranu's user avatar
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Related to dimension of wireless channel , transmitted signal and received signal

I am working on wireless research project and I had query in understanding dimensions. Consider a MIMO system, where a base station with $N$ antennas transmits signal $x$ to receiver with $M$ antennas....
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Related to SNR in wireless communication

I am working on a research paper related to wireless communication, wherein I am facing some doubt while writing expression of SNR (which is a ratio of Signal variance in numerator to Noise variance ...
Pranu's user avatar
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Regarding SINR (Signal to Interference Plus Noise Ratio) in wireless communication

I am working on a research paper related to wireless communication, wherein I am facing some doubt while writing expression of SINR (which is a ratio of Signal variance in numerator to Interference ...
Pranu's user avatar
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Channel impulse response (CIR) and OFDM relationship

In Chapter 3 of the [Goldsmith book] (https://faee.sut.ac.ir/Downloads/AcademicStaff/1/Courses/7/Andrea%20Goldsmith-Wireless%20Communications-Cambridge%20University%20Press%20(2005).pdf) we can see ...
rick87's user avatar
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1 answer
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Transmit/receive signal of two-path propagation model

In wireless communication, when the transmitted signal is $x$ and the received signal is $y$. Please tell me why the formula below holds true. \begin{align} y(t) &= \left( e^{-\jmath 2\pi f_c\...
Ryo Onishi's user avatar
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83 views

Channel equalization in uplink

I have a multiuser uplink signal $$ Y=h_1x_1+h_2x_2$$ where, $h_1$ and $h_2$ are channels for user 1 and user2 respectively. At the receiver how can I equalize the signal $Y$, assuming known $h_1$and $...
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How to determine Transmission Rate for Task Offloading in edge computing?

I am new to communication systems and am working on a model for task offloading on edge computing. One key parameter I'm aiming to determine is the data transmission rate. While I am familiar with ...
user4594525's user avatar
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How to calculate capacity using Shannon and path-loss?

I am working on tasks offloading on edge computing. I need to find the transmission delay, through calculating Shannon capacity-theoretical maximum data rate- when sending results from the server back ...
user4594525's user avatar
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1 answer
54 views

How to understand Fading Channel with no CSI at the Receiver

From the book Fundamentals of Massive MIMO, the section 2.3.4 shows that the expression of the received signal in fading channel with additive non-Gaussian noise and no CSI at receiver is dervied as: $...
Loco Citato's user avatar
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fractionally spaced channel equalizer code [closed]

I want to write a program in matlab for an adaptive fractionally spaced equalizer with lms algorithm.consider each packet with 150 bits that 25 first bits are pilot and used to train weights of the ...
Mahtab's user avatar
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1 answer
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Rayleigh flat fading channel and pulse shaping

I'm trying to implement the Rayleigh flat fading channel in MATLAB using SRRC (Square-root raised cosine) pulse shape. The modulation scheme is BPSK. Here is my code: ...
S.H.W's user avatar
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How do random processes add in Rayleigh fading to get a Guassian random process?

I was studying Rayleigh channels from Wireless Communications, Second Edition by Andreas F. Molisch. The book states that by adding different in-phase and quadrature components multipath components ...
mahmoud esmail's user avatar
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3 answers
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which type of diversity is used by rake receivers?

My question is: Which type of diversity technique is used by the rake receivers? In Bahai, et. al. "Multi-Carrier Digital Communications Theory and Applications of OFDM," Second Edition, ...
Ali's user avatar
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Which are the realictic enviroment will be suitable for TDLC300 channel model?

TR 38.901 Section 7.7.2 mentioned that the TDL-A, TDL-B, and TDL-C channel models are constructed for NLOS scenarios. In TS 38.101-4 Annex B.2.1, in Table B.2.1.1-1 (picture is attached), delay ...
Aragorn's user avatar
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1 answer
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How to code Rician fading channel gains from k-factor?

I know that MATLAB provides some built-in functions but I am not interested in those. I want to know how can we code to obtain the Rician fading channel gains from normal or Gaussian distributions. ...
ZZ1's user avatar
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Elevation angle or Azimuth angle?

Suppose my ULA(Uniform Linear Array) is along x-axis only, then definitely we can estimate elevation angle with this ULA. But if we lift this array from x-axis and place it along y-axis, then which ...
matlabbeginner's user avatar
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What is physical significance of Bit Error Rate (BER) and Outage Probability?

I am trying to understand the physical significance of Bit Error Rate (BER) and Outage Probability especially in low power wireless communication such as internet of things (IoT). Any help in this ...
chaaru's user avatar
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2 answers
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$\min(\{Z_i\})$ for non-i.i.d. random variables $Z_i$ the same as for i.i.d.?

My question is with reference to wireless communication. There are $N$ independent and identically distributed random channels i.e., $Z_i \in \{ Z_1, Z_2,\ldots, Z_N\}$ with PDFs $f_{Z_i}(z)$ ordered ...
chaaru's user avatar
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Order statistics: always applicable tool in wireless communication?

I have seen few papers where generalized order statistics is used to obtain statistics of the instantaneous SNR. "Performance analysis of monostatic multi-tag backscatter systems with general ...
chaaru's user avatar
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1 vote
1 answer
58 views

Understanding Pathloss and latency

In my class on wireless communication, I came across the following sentence: The round trip path-loss can be defined to include aspects such as attenuation and/or latency etc Hence I am looking for ...
chaaru's user avatar
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Related to wireless channel variance?

I am reading wireless research papers and found that mostly the wireless channel is considered to be Zero mean circularly symmetric Complex Gaussian (ZMCSCG) with variance 1 or 2 or 5 or 10 etc. My ...
chaaru's user avatar
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0 answers
71 views

Understanding mathematical representation of SINR

I am getting confused in SINR for the following received signal expression. $$y(n) = (h+fg)s(n) + w(n) \tag{1}$$ Where $h,f,g$ are zero mean circularly symmetric Complex Gaussian (ZMCSCG) channels. ...
paru's user avatar
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1 answer
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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 ...
paru's user avatar
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1 vote
2 answers
513 views

Why exponential decay power delay profiles are used to model fading?

I am trying to understand why exponential decay power delay profiles are used to model fading. In other words, why power of taps of channel impulse response decays exponentially and not, for instance, ...
Pawel's user avatar
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Derivation of Clarke's Doppler power spectral density

I am reading Wireless Communications by Andrea Goldsmith. I have some issues in the derivation of Clarke's Doppler power spectral density given there. 1)For beginning the autocorrelation of the in ...
UserHuffmann's user avatar
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Derivation of equation 3.8 in Fundamentals of Wireless Communication by Tse and Vishwanath

In the book “Fundamentals of Wireless communication”by Tse and Vishwanath, Can someone help with the how the integration helps derive equation 3.8 ? The equation is $$ p_e= \mathbb P\left\{\left\lvert ...
Vageesh Dambal's user avatar
1 vote
0 answers
50 views

How to resolve some inconsistencies in the mathematical model for the narrowband fading channel?

I am reading Wireless Communications by Andrea Goldsmith. There the author mentions that for narrow band channel the received signal can be given as: $$r(t)=\text{Re} \left\{u(t)\text{exp}(j2\pi f_ct)\...
UserHuffmann's user avatar
1 vote
1 answer
65 views

On-Off keying for wireless communication channel estimation

Let us assume I have $k$ (a fixed number) sensors in a wireless sensor network with unknown channel statistics $\{h_1,h_2 \ldots, h_k\}$. In my system model, each of these $k$ sensors has an ...
wanderer's user avatar
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0 answers
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Coherent detection in fading channel

I want to design an optimum receiver for a fading AWGN channel for ML Detection. I know that in the case of non-coherent communication we have to use an energy detector(even when the fading channel is ...
indmath's user avatar
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1 answer
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Log Path Loss Model with Directivity Accounted

Suppose that I have the log Path Loss distance model described here https://en.wikipedia.org/wiki/Log-distance_path_loss_model $$PL(d,\gamma) = P_{t}-P_{r}=PL_{0}+10\gamma log_{10}\frac{d}{d_{0}}+X_{g}...
Jonathan1234's user avatar
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1 answer
451 views

Relation between SNR and fading channel coefficients?

I am trying to understand the following thing: Does the average signal to noise ratio (SNR) depends on fading channel coefficients ? Any help in this regard will be highly appreciated.
Saru's user avatar
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Related to successive interference cancellation?

I am trying to understand the following query: " Is it necessary to do channel estimation to perform successive interference cancellation at the receiver operating over fading channel" Any ...
Saru's user avatar
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1 vote
1 answer
8k views

What are TDL and CDL channel models in principle, and which variation can be used for indoor and outdoor environment, respectively?

I am making a simulation using 5G-toolbox in Matlab. IN 5Gtoolbox we have two kind of channels, CDLChannel and TDLChannel. Now, CDL means Clusteresd Delay Line, and TDL means Tapped Delay Lines. But ...
SJa's user avatar
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0 answers
178 views

Frame synchronization for single carrier burst applications in fading channels

I recently started to implement communication systems with software-defined radios in GNU Radio. In my system design, I am planning to transmit data in burst mode, the frames will be not sequentially ...
Okan Erturk's user avatar
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1 answer
175 views

Log-normal shadowing and mean power

Let's assume I'm receiving a signal with power measured in dBm shadowed according to the normal distribution, i.e. $P_{\text{dBm}} \sim N(0,1) $. If there is also a normally distributed noise power $...
Mundo's user avatar
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1 vote
2 answers
542 views

Rayleigh Fading

I am calculating the capacity of $K$ channels between a transmitter and $N$ receivers in a cellular scenario. I use the following equation: $$C_n^k = B\log_2\left(1 + \frac{Ph_n^k}{N_0B + I_n^k}\right)...
Kasparov92's user avatar
1 vote
1 answer
321 views

Related to channel power gain

I am having a doubt that why channel power gain is denoted by $|h|^2$. For example, if the signal received is $$y(n) = hx(n)+w(n)$$ where $x(n)$ is transmitted signal with power $P$ , $w(n)$ is AWGN ...
paru's user avatar
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-1 votes
2 answers
90 views

How is the distribution of the received signal affected if the transmitted signal is changed from complex Gaussian to PSK

Suppose the received signal is $y(n) = h_0s(n)+w(n)$----(1) Where $h_0, s(n), w(n)$ all are distributed as zero mean complex Gaussian. Thus I know that $y(n)$ will also have the same distribution. If $...
paru's user avatar
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1 answer
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understanding the distribution of received signal

In one of the research paper following equations are given : $y(n) = h_0s(n)+w(n),d = 0$ $y(n) = h_1s(n)+w(n),d = 1$ where $n$ ranges from $1$ to $N$ and $h_0,h_1$ are wireless channel assumed as $\...
paru's user avatar
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0 answers
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Related to wireless channel fading

I am reading some papers wherein a wireless channel is assumed as zero mean circularly symmetric complex Gaussian (ZMCSCG) with unit variance and it is also mentioned that the channel undergoes ...
paru's user avatar
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0 votes
1 answer
68 views

related to random nature of wireless channel

I am reading An Approximate BER Analysis for Ambient Backscatter Communication Systems With Tag Selection wherein it is mentioned that "when the distance between two nodes is very small and line ...
paru's user avatar
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0 votes
1 answer
636 views

What is the meaning of the channel gain is normalized

Transmitting the signal $x$ over the channel $h$ and affected by noise $n$ can be expressed: $y = hx + n$ $h$ is the channel gain, that is known for me. I sometimes see phrases saying "when the ...
New_student's user avatar
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1 answer
115 views

bit reversed order of FFT matrix for channel estimation

Although the question seems similar to this one HERE, but what I want to ask about is little bit different. Assume we have a signal $X$ whose length is $N$x$1$, we convert that signal into time ...
New_student's user avatar
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1 answer
259 views

How is channel frequency response/channel state information related to free space path loss?

As we know, the path loss can be described by the equation as $$ \frac{P_{r}}{P_{t}}=D_{t} D_{r}\left(\frac{\lambda}{4 \pi d}\right)^{2} $$ In the OFDM system, such as Wi-Fi, there are infinite paths ...
ColinGuolin's user avatar
3 votes
0 answers
249 views

About discrete time model for wireless channel

I am trying to understand Section 2.2.3 of the book "Fundamentals of wireless communication" by Tse and Viswanath. In this section the authors explain how to go from the continuous time ...
Coniferous's user avatar