Questions tagged [sampling]
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225
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ADC of TM4C123GH6PM( 1 Msps as given in datasheet ) is not reading any data if sampling frequency is increased beyond 250Khz
I need to sense a signal at 500kHz.
According to the datasheet of the TM4C123GH6PM it is able to sample up to 1000Khz.
The code is already written with sampling frequency at 90Khz. Whenever I ...
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1answer
24 views
How to enable the DMP of the MPU9250?
The datasheet mentions some Advanced Hardware Features which gets executed by the Digital Motion Processor. I'd like to use the ...
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34 views
How to transmit the data from the buffer filled with ADC values through DMA on STM32F7
I am currently trying to a sample a signal between 25-40kHz with three microphones to calculate the time difference.
I'm having difficulites understanding what to do after the ADC is activated and ...
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1answer
54 views
the minimum cable bandwidth [closed]
In a sound recording studio 11 microphones are placed at different locations. The data from each microphones are brought to a processing center over wires and are sampled, quantized, binary coded and ...
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46 views
Sampling Capacitor In INA
I am looking at parts like the LTC2053 which use a sampling capacitor on their input. I had a few questions:
Does the input impedance of this amplifier simply look like the sampling capacitor (1000pF)...
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1answer
51 views
Relationship between switching frequency and controller's crossover frequency in DC-DC converters
I am reading some answers related to my questions based on control loop stability of SMPS.
I came across this question.
The accepted answer states:
A switch mode power supply is essentially a ...
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2answers
134 views
I2C data sampling is done at clock edge or level
I am trying to understand I2C data bus from this document. It explains the START-SLAVEADRESS-R/W-ACK-DATA.. as the master-slave take turns to get hold of the shared bus for mutual communication.
One ...
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5answers
134 views
Sampling theorem clarifications
whenever the sampling theorem was explained to me, a situation of this kind was proposed to me.
If we look at the previous image we will see that the condition to avoid spectral aliasing is that we ...
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54 views
Huge spikes and sudden offset in accelerometer data (FRDM-K64F & ADXL357)
I'm working with vibration analysis on electric motors (AC). I have a mBed FRDM-K64F with a EVAL-ADXL357 connected to it - mounted onto a motor.
The device samples from the FIFO 4000 times per second,...
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1answer
30 views
Relation between spectral leakage and the frequency of harmonics of a signal
I'm currently studying "Data Acquisition".
I read that when we have frequency/spectral resolution equal to a natural number, there will be no spectral leakage, for none of the harmonics.
However the ...
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53 views
Sampling Frequency of a pulsed radar signal
I'm new to radar. please excuse my question if it doesn't make sense to you.
In a pulsed radar signal, why is the required sampling frequency "2 times the inverse of pulse width" instead of "2 times ...
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1answer
47 views
Accurate signal reconstruction
While reading through this page I came across following info:
"For accurate reconstruction using sin (x)/x interpolation, your oscilloscope should have a sample rate at least 2.5 times the highest ...
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27 views
How to measure the amount of light emitted back from a fiber optic cable?
I would like to build a setup where I use a light source to emit a signal over a fiber optic cable, and then measure the amount of light that is emitted back, e.g. by blocking/opening the other end of ...
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1answer
32 views
What are the appropriate pulse width and PRF for a pulsed Doppler sensor
I have a raw k-band transceiver, radar-based 24 GHz, motion detector, IPM-165.
and here is the datasheet:
https://www.innosent.de/fileadmin/media/dokumente/DATASHEETS_2016/Datenblatt_IPM-165_V8....
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2answers
57 views
How to measure or estimate the phase delay between two analog input channels of this board?
There is a 16-bit data acquisition board with +/-10V range which multiplexes analog inputs and buffers the data to the PC. Specifications are given here (DAS6036 is the model in question).
Now I need ...
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0answers
28 views
Necessity of PDM processing on the data given by an interfaced condenser microphone through ADC channel on stm32f4 discovery
I want to interface a condenser microphone with my stm32f407vg discovery board and obtain the audio output through the DAC audio jack. For the audio processing should I first convert the input digital ...
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4answers
3k views
Can sampling rate be a floating point number?
Suppose we have a sampling frequency for a signal of 15.5 samples/sec and we take samples for a period of 7 seconds. This means total samples are 108.5, does this make any sense?
Shouldn't the ...
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1answer
76 views
Relation data-rate and bit-rate of ADC
I came accross the folowing question, where the accepted answer contains a formula showing the relation between bit-rate and data-rate for a delta sigma ADC. My question is, why that relation is valid....
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1answer
58 views
Sampling Frequency and Bandwidth
If i have a Buck Regulator switching at 200KHz and i want to sample the Voltage and current using OpAmp in tha path connected to ADC(12 bit).
What would be the sampling frequency to measure the ...
0
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1answer
78 views
basic DIY function generator and scope
I'm currently traveling and only have access to basic parts (soldering iron, an arduino nano and a breadboard!) but I'm able to buy parts from local suppliers. for a project I need to be able to ...
0
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1answer
37 views
How does a fiber optic receiver converts the optical signal to an electrical signal
A fiber optic receiver needs to convert the incoming optical signal to an electrical signal so it can be sampled. How is this achieved in practice?
I believe a photodiode is used, but would a ...
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47 views
Sampling Frequency of a delta-sigma ADC
For instance, let's take this delta-sigma ADC:
http://ww1.microchip.com/downloads/en/DeviceDoc/22088c.pdf
To calculate the average current and other important values for various sampling scenarios I ...
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2answers
231 views
Filtering an ADC input with an RC low-pass filter
I use an instrumentation amplifier to amplify low voltage signals from a sensor.
The max. amplified output voltage is 3V. Im using this ADC: http://ww1.microchip.com/downloads/en/DeviceDoc/22088c.pdf.
...
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2answers
90 views
thoughts on reading only one changing GPIO with accurate time amoung huge number of digital Inputs
I am trying to read a huge number of digital inputs (129 to 800 and maybe more) at the same time. the sampling rate should be around 500K samples per second but I only need to read one of these inputs ...
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1answer
38 views
ADC bandwidth in excess of filter bandwidth
I am using a BPF of 5 to 300kHz on a pulsed input signal. Is there any benefit to digitizing at a rate significantly in excess of nyquist?
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1answer
50 views
First-order hold interpolation in matlab
I have a sinusoidal signal x(t) sampled with period 1/fs. The result is the discrete signal x[n], where x[n]=x(t)|t=nT. Then I perform an upsampling of factor, let's say, 8 to increase the sampling ...
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2answers
247 views
increase the ADC resolution using oversampling [duplicate]
To increase the ADC resolution, oversampling technique can be used which must be followed by decimation (average) method.
Oversampling is just take several samples within time period. Unlike the ...
11
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6answers
2k views
Why does increasing the sampling rate make implementing an anti-aliasing filter easier?
From an answer to a question regarding sampling rate and anti-aliasing filter I read the following:
The closer you get to the theoretical minimum sample rate, the more
difficult the analog filter ...
0
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3answers
84 views
Fastest temperature sensor for a bimetallic strip
What is the best approach or sensor to analyze the temperature of a bimetallic strip?
From experimental data, the temperature swings due to a current flowing into the bimetal, are up to 80°C in a ...
0
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2answers
135 views
New Amazon music streaming service and Nyquist sampling theorem [closed]
I read this story on The Verge the other day,
“It’s a better bitrate, better than CD quality,” said one of MBW’s sources, indicating the new service will put Amazon in direct competition with Tidal’...
0
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1answer
35 views
Input voltage on differential ADC (MCP33131D-05-E/MS)
I am evaluating a 16bit ADC (MCP33131D-05-E/MS) for my project. I want to sample in fully differential mode, but I have doubts as to what voltages are allowed on the Ain+ and Ain-.
Signal ...
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1answer
82 views
Calculating sampling frequency off of estimated stop band attenuation
I'm trying to calculate what I will have to set my microcontroller's ADC sampling rate at in order to sample a band of 500kHz to 1.6065MHz without aliasing. Some constraints here are that I have to ...
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4answers
803 views
Is there an efficient way for synchronising audio events real-time with LEDs using an MCU?
I'm working on a project in which LED lights synchronise with audio events. I'm not referring to reactive LED projects that read the ADC from audio amplitude or spectrum, but about having some ...
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0answers
31 views
Data synchronization strategy for multiple sensors in BLE application
I am working on a battery sensitive BLE project which combines the MAX30003 ECG sensor and the LSM6DS3 accelerometer. Communication with both of these devices is made through SPI. The optimal sampling ...
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1answer
69 views
Possibility of effectively under sampling a band pass signal?
For a university project we have been tasked with implementing a digital signal processing system on an STM32 discovery board in which we must model the AM channel to measure and graphically display ...
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2answers
119 views
Maximum information Rate? [closed]
It is said that we can transmit at the most twice as many bits information per second as the transmission channel has the bandwidth. For example, 1 kHz bandwidth allows max 2kbit/s, if that rule is ...
4
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4answers
130 views
Sampling Theorem and reconstruction
I do not understand a concept about the Nyquist - Shannon sampling theorem.
It says that it is possibile to perfectly get the original analog signal from the signal obtained by sampling if and only ...
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0answers
53 views
Wifi versus Zigbee versus Bluetooth for real-time data sampling
I am working on a project that I would like to send and receive data between a microcontroller (ESP32) and a PC. The microcontroller supports both Wifi and Bluetooth. If I send one single data point (...
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20 views
sampling rate and bit resolution for Scanning Probe Microscopy
I am trying to compare two products and see which one offers higher performance in terms of sampling rate and bit resolution.
Below are the specs I was able to gather from product1 and product 2. (...
2
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1answer
36 views
Sampled offset voltage data and its uncertainty
In a measurement process sometimes contant voltage output of a for example force transducer is logged as offset as a bias to be subtracted later from the dynamic measurement. When the sensor is at ...
0
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1answer
105 views
Logic Analysis of a 8 bit mcu [closed]
I would like to sample the logic on the pins out out of a toy robot's processor and the MCU is an 8 bit processor that operates a max clock speed of 5 Mhz.
Does anyone have any recommendations on how ...
2
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0answers
50 views
Increasing SNR through sampling and coherent integration
Let's say I have simple BPSK scheme and a receiver RF stage such that I have an ideal analogue bandpass filter with bandwidth \$ f_{bw} \$ and then a down converter and finally a sampler. I am trying ...
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2answers
171 views
How do we compute power from current and voltage samples? Can we quantify its accuracy?
I have a datalogger that periodically samples current values by measuring the voltage across a power resistor connected in series with a battery and sensor (the load). The datalogger also samples the ...
0
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1answer
51 views
Is it possible to use one DAC to process signals from different channels that are delayed at different times?=
So I have a small project where I need to delay multiple signals that come out from a microcontroller. The signals are around 40kHz, have the same attributes, except that they are delayed by a few ...
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3answers
140 views
Do I need to filter before sending signal to an ADC?
I have an ADC that is capable of a 25kHz sample rate and I have a sensor whose bandwidth is 200kHz that I'd like to hook up to. This is a current sensor. Nyquist tells me that I need to limit the ...
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1answer
138 views
why gyroscope sample rate can be changed by frequency, while accelerometer sample rate cannot?
This is from the mpu6050 datasheet.
In the datasheet, gyroscope sample rate can be changed by frequency, but accelerometer cannot.
Why this happens?
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1answer
132 views
Sample time of PI controller
I have designed a closed loop current control (PI controller) of a DC-DC converter in continuous time domain and it is working fine. The next task is discreetization of the controller and implement it ...
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3answers
247 views
How to obtain Input voltage from ADC value
I am using atmega328p for my project. I have to read my battery voltage and display it in my cloud. For that, i am using ADC. Now I am getting the ADC value for input voltage applied. But i need to ...
0
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3answers
217 views
Understanding the effect of bit depth and sampling rate on SNR
I know the meaning of a 16 bit ADC sampling at 1kHz, but I cannot relate it to SNR contribution to the signal. I also know the concept of aliasing. But even though no aliasing the resolution and the ...
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1answer
46 views
regarding the sampling frequence
In my project I am using PIC32MX250F128B controller and 23LC1024 SRAM. I have written a code to sample the analog signal from the vibration sensor. For this I am triggering my ADC with the help of ...
