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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 ...
• 223
27 views

### 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 ...
1 vote
60 views

### 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 ...
19 views

### 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 ...
42 views

### 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 ...
17 views

### 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....
39 views

### 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 ...
51 views

### 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 ...
1 vote
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1 vote
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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\...
1 vote
83 views

1 vote
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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 ...
• 11
239 views

### 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: ...
• 726
149 views

### 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 ...
1 vote
85 views

### 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, ...
• 95
175 views

### 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 ...
• 135
1k views

### 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. ...
• 23
433 views

### 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 ...
121 views

### 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 ...
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36 views

### $\min(\{Z_i\})$ 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 ...
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44 views

### 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 ...
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1 vote
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 ...
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78 views

### 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 ...
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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. ...
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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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1 vote
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, ...
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249 views

### 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 ...
73 views

1 vote
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 ...
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103 views

### 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 ...
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• 141
1 vote
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 ...
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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 ...
• 17
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 ...
• 17
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 ...
• 639
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 ...
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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 ...