Questions tagged [network]
The network tag has no usage guidance.
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1answer
47 views
How to understand Transmission and Propogation delay formula
I have three questions below. I would like to understand how their respective answers were reached, this is a question in my current class and everyone in the class has A-Level mathematics experience -...
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0answers
31 views
Determine Y-parameters for given circuit. [Used Nodal Analysis]
I am trying to solve this circuit for past 3 hours, no success, so I am posting here.
simulate this circuit – Schematic created using CircuitLab
I used nodal analysis, I will go over the ...
0
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1answer
48 views
Trouble with instrumentation and simulation of the common-mode response of a filter
I have been struggling to obtain the Bode plot of common-mode response of a filter. I first simulated it using LTspice, then I used a USB network analyzer. Both do not match each other and to the ...
1
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1answer
74 views
Calculating total resistance between two points (triangle resistor network)
I want to calculate the total resistance between the 2 points: A, B.
I've tried using the Delta-Wye method, but I'm not sure how to apply it to my problem since there's 6 resistors and not 3 (usually ...
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0answers
30 views
How to use JDY BLE modules for Bluetooth mesh networking?
I bought some JDY-21,JDY-19, JDY-18 and JDY-17 modules.
All of them support Bluetooth 4.2 LE. Some module claim to be able to use mesh with them. So, I watched this video about Bluetooth mesh networks....
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0answers
12 views
deriving an equation for wireless network capacity
I'm trying to derive an equation for wireless network capacity given topological constraints of the nodes and certain obstacles... but before I get that far, I want to understand the most simple case. ...
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1answer
24 views
Can a dependent voltage/current source have some impedence/admittance,respectively?
Im studying 2-port networks, for Z parameters equations, there is general equivalent circuit given, in which dependent voltage source is given, I do know about dependent voltage sources, but do these ...
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2answers
33 views
Network Analysis for finding power delivered
We need to find the power delivered by the 5V source in the above network. I usually apply superposition theorem when I need to find the power delivered by a source when there are many power sources ...
1
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1answer
62 views
Calculating input impedance of 3 port network
I am trying to derive a expression for calculating the input impedance of a 3 port network to use as direct calculating code and avoid SPICE/simulator solving of the same.
I am able to solve the ...
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1answer
40 views
Purpose of Bus Analyzer
I've not found the clear explanation for the WHY we use the bus analyzer except to capture and analyze data across the communication bus. Yes, we observe message structure, such as command words, ...
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2answers
92 views
How to determine the physical location on a RS-485 daisy chain / bus topology?
I am trying to build a "daisy chain" using several Arduinos and MAX485 transceivers. All boards have a temperature sensor attached to it. A 9V battery supply all boards in the chain.
I am trying to ...
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2answers
74 views
What communication method shouild I use [closed]
So I wan to control a bunch of devices.
I though first of using RS485 but after some digging I figured out this might not work as I don't really have a pure daisy chain.
The configuration I would like ...
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3answers
53 views
Hardware requirements for 10Gbps line rate packet processing
How do I calculate the horse power required for worst case packet processing scenarios?
First, a little more background, I'm building a device for packet analysis. My test box currently runs on Linux ...
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0answers
82 views
HR911105A connector problem!
I have a stm32f407 microcontroller and I want to use ethernet with DP83848 physical layer. Finally I have HR911105A and when I pluged in and program the microcontroller, when I want to ping, it did ...
0
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1answer
57 views
Impedance Matching Network with tracks+connectors in between (practice)
I've been struggling on how to design (and develop in practice) an impedance matching network with some traces/tracks/paths (whatever you wanna call it) and some connectors in between. So here is the ...
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0answers
35 views
Bounds of impedance matrix of a passive two port network
If we consider the impedance matrix of a linear, reciprocal passive network (Z12 =Z21 because of the reciprocity),
$$
\begin{bmatrix}
Z_{11} &
Z_{12} \\
Z_{12} &
Z_{22}
\...
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0answers
118 views
How to get the transfer function of electrical network using nodal method
We have the following circuit:
I am trying to get the transfer function using the Mesh Method. The first equation I've got is:
(s+1) I1(s) - sI2(s) = Vi(s)
The ...
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1answer
69 views
Resistance or conductance of resistor networks
I am trying to figure out if the equivalent resistance (or similarly conductance) of a resistor network can be calculated using Qucs (as opposed to solving the Kirchhoff equations directly, or doing ...
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5answers
593 views
Is there a wireless protocol for 100m-1km range in rural property?
I am an electornics hobbyist. A friend of mine, who is building an organics farm, wants to wirelessly automate some devices in his property, and asked for ideas.
His problem is to "talk" to remote ...
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3answers
25 views
power network consumption vs network resistance [closed]
I have a simple question. Based on Ohm's law, \$V=I\cdot R\$, by increasing the resistance, if the voltage is fixed, the current will drop. By dropping current, the consumption or the loss will drop (\...
0
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1answer
67 views
Transmission and propagation
Two stations are 400km apart from each other. You have access to a 100Mbit/s full duplex radio link which transmits packet of 4000 Bytes in each direction.
What is the transmission time?
I assume ...
25
votes
8answers
9k views
Why not implement 1Gbps, when all I need is 20Mbps?
Background
I am working with a client on a large project which requires a custom networking chip to be designed to solve the data transfer requirements within the project. The network is intended to ...
0
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2answers
135 views
What are the different antenna types used by various IEEE 802.11 standards?
I've been working on an assignment about the IEEE 802.11 standards and I've had some trouble with one aspect of a question. I need to explain the differences between various features of the different ...
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0answers
19 views
Orientation of eNode antennas
What type of omni-directional antennas is used at an LTE base station, also known as eNode? and What is the orientation of such antennas? and how come the 3GPP path-loss model for such antennas is ...
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0answers
30 views
Medium length transmission pi model
My question is regarding medium length transmission line calculations, hopefully someone has studied them.
Usually I am given the voltage, active power and power factor at the receiving end of a ...
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0answers
20 views
Practical assumptions for accomodating cellular, D2D and M2M devices
Question: Given Assumption 1 in a network model which accommodates device-to-device (D2D) communication within a cellular network in the underlay and overlay, make an assumption to accommodate machine-...
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3answers
244 views
Kirchoffs Law for 3 Loop Circuit with Multiple Voltage Supplies
I am working on the below circuit to find; the power dissipated by RL (8Ω resistor), voltage drop across RL and current supplied by the 10 volt battery (V1).
So far I have used Kirchoff's law to the ...
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0answers
392 views
How to create a J1939 ID that have a PGN = 0x130?
I'm trying to create a J1939 message with a PGN equal to 130.
But I couldn't determine how the ID is going to look like in order to get that exact PGN.
Can you please share a suggestion?
Thanks a ...
-1
votes
1answer
67 views
Determining the voltage of a network branch
[NOTE-This is a not a homework problem and i am not asking anyone to solve it]
Recently I have been simulating some basic circuit analysis problems in a simulator to get a better feel of the topic....
1
vote
2answers
62 views
Interactions between Ideal Voltage and Current Sources
Last week I asked a question involving a linear network involving ideal current and voltage sources. You guys gave me some great advice as to how to approach those types of problems. However, this ...
0
votes
1answer
93 views
How to explain why equivalent resistance between two points in this network is dependent on specific resistance?
The original network is an square network with two diagonals as you can see here there is no intersection between the diagonals.:
The question is what is the equivalent resistance between points A ...
1
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1answer
332 views
Altium hierarchical design assigning net to power port/port
I have a hierachical multichannel design and I´m having problems to set properly the project properties so that the following issue is removed.
As you can see one of the ports of the child sheet is ...
0
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1answer
344 views
Finding voltage drop on a resistance using mesh analysis
How to find out Vx on the specified resistance using mesh analysis?
simulate this circuit – Schematic created using CircuitLab
Here Vx is to be found out on the 1 ohm resistor.
I tried ...
3
votes
1answer
153 views
Finding out unknown voltage using mesh analysis
How to find out the voltage v3 in the following circuit using mesh analysis?
I tried to solve it by considering the dependent current source as a super mesh and eliminated it.
The equations I got ...
0
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0answers
193 views
Problem in connecting to a server waiting for a TCP request using ESP8266
I'm using ESP8266 for connecting to a appspot-preview.l.google.com server which listens for TCP request and answers back a number (it's for training purposes).
...
17
votes
3answers
2k views
What is the underlying mechanism behind Wi-Fi getting slower with greater distance?
It's common knowledge that the further you go from a Wi-Fi network point, the slower the network over Wi-Fi gets. But why would this be the case? Radio signals propagate at essentially the speed of ...
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0answers
109 views
Ouput impedance of a balun
I am using the CC1110 RF IC and I am having trouble when matching the differential RF output impedance with the antenna. The datasheet states that the differential impedance seen from the RF output ...
0
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2answers
283 views
KSZ8895 Switch-Circuit Problem
For an application I am trying to get a switch running using the KSZ8895 (standalone). For testing, at first, I connected it only to MagJacks.
If I test the circuit and connect two PCs, this worked (...
1
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1answer
96 views
Can we do source transformation for dependent sources? [closed]
In network analysis, during source transformation for dependent sources
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1answer
80 views
Can you use a amplifier and a satellite antenna to boost a GSM signal?
I have a small GSM Modem whose internal antenna sucks. I bought a small external antenna that boosted the signal a little, however I want to boost it more. Would using a typical high frequency audio ...
2
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0answers
280 views
Bus interface for short distances, many device data exchange - CAN, RS485? + characteristic impedance and media capacitance
I ran into some troubles trying to design a wired bus which will connect in about 64 testing devices. My first choice of mind was CAN bus, known of it's reliability and low EMC interference. However, ...
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votes
1answer
62 views
Why sometimes I have voice but no data on a GSM network? [closed]
From what I understand, both voice and data are using the same antenna (At least 3G).
Sometimes in a remote area, I have plenty of signal but no data service.
Is it possible some cell towers don't ...
0
votes
1answer
48 views
What is the role of a Network Interface Device in a ADSL connection?
What is the role of a Network Interface Device in a ADSL connection?
Why the filter is not enough? What is the difference between them?
0
votes
1answer
93 views
Power over Ethernet identification error?
I have a custom board which is powered by Ethernet and I am using the LT4275B from Linear using the recommended schematic.
When I am using a cable with only the data pairs [1-2]&[3-6] ([4-5]&[...
0
votes
1answer
83 views
S parameters measurement inside VNA
How does Vector Network Analyzer (VNA) measures S parameters in reality?
Namely we have equations:
\$b_1=S_{11}a_1+S_{12}a_2\$
\$b_2=S_{12}a_1+S_{22}a_2 \$
In theory, if i wanted to calculate ...
0
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0answers
71 views
Can cell phones be reprogrammed for peer-to-peer connectivity avoiding carrier base stations to create a free meshed network? [duplicate]
In light of recent events concerning the freedom of internet, thoughts are going in the direction of breaking free from the control of wired internet service providers. One widely discussed option is ...
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2answers
535 views
Difference between 2.4Ghz ISM and IEEE 802.11 frequency bands?
It may be a silly question to ask the difference between a frequency band and a standard protocol which is represented by IEEE.
But, I've been reading the wikipedia page of the IEEE 802.11 and it says ...
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0answers
40 views
Failure for parallel - parallel two-port network
I'd like to know what's the simplest example of two-port parallel-parallel network that fails Y=Ya+Yb.
Just as two T networks fail series-series connection, I thought that two Pi network would fail ...
0
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1answer
74 views
How to represent binary for differential and Menchester coding?
I have some questions with solution provided from random material, but I can't understand well.
Question 1:
I tried to represent binary for each block according to description in the picture above, ...
1
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2answers
98 views
Correct definition of transition in line coding
Hello I have following question and it says:
I basically cannot understand this solution.
My questions:
isn't it a sequence of 4 0s followed by 4 1s? (answer says 4 1s followed by 4 0s) since ...
