Questions tagged [dsp]
DSP stands for Digital Signal Processing or Digital Signal Processor.
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questions with no upvoted or accepted answers
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FIR Lattice Filters
In DSP, sometimes the so-called Lattice Filters are use, having a structure like on this picture:
I wonder what the advantages of the Lattice structure are, compared to other FIR filter types and ...
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Why does a cosine function have a non-infinite Fourier coefficient?
I took my signals class a long time ago and have gotten used to using Fourier tables for a lot of things. I'm reading a textbook on communications and I stared at the Fourier transform equation for a ...
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Adding Line Out / Sub Out to LG soundbar
I have LG Soundbar with wireless sub. I am trying to add Line output, so i could connect a wired sub.
I took some pictures of the boards and chips. If someone could point me in right direction on ...
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How to amplify the output of a digital low pass filter?
I have used the transfer function of a RC low pass filter to design a IIR Digital low pass filter.
\begin{equation}
H(s)=
\frac{1}{sRC+1}
;First
\space
order
\end{equation}
\begin{equation}
H(s)=
\...
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RC filter - compute output as a function of input for generating waveform
I'm not so deeply into the theory about all this, I may use strange terminology...
If I put a square wave through a simple lowpass RC filter, the output will be a sort of "rounded sawtooth", well not ...
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PCM5242 DAC: DSP Program and DSP Frequency for high sampling rates
I want to use a PCM5242 DAC (datasheet) in a project
The DAC has a built in DSP core that I don't want to use for anything custom.
The DSP can be programmed with custom code, or predefined codes in ...
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77
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Tuning controllers in dual-loop control with feed-forward and decoupling signals
What would be the best step-by-step approach to tune PI controllers in a dual-loop control with decoupling and feed-forward signals?
I am trying to tune both the voltage and current controller in DSP ...
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Relative error of power estimation
I'm reading my teacher code for FFT windowing in Matlab and there is one thing I don't understand. When you run the code at the end it says:
...
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Best way to output n digital signals using n-1 DAC channels
I have 3 digital signals that need to be mixed and output into the analog domain. My DAC has 2 channels (Left and Right).
The way I see it, I can:
mix the signals 1, 2, and 3 digitally and output ...
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1
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How to measure the time it takes to receive a new sample from CODEC using a fixed sample rate of 48kHz?
in my current set up I have a CODEC set as master connected to my STM32F446RE (slave).
The current configuration utilizes I2S DMA interrupt callbacks to handle the input and processing of these ...
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1
answer
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Discrete time decimation bandwidth expansion
I have been reading about discrete time decimation in Signal and Systems by A.Oppenheim. The decimation process expands/scales the bandwidth of the original non-decimated signal by N, I have a hard ...
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Lattice FPGA: Mach X02 7000 Can it be used for DSP?
I have a MachX02 7000 having 6800 LUT's.
I want to implement DSP algorithm involving floating-point DSP algorithm on 2 14 bit ADC input data.
Is it possible to perform on this FPGA with low LUT's, No ...
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How does stretch processing work for SFCW?
I've been reading about FMCW radar, and I understand that a chirped signal can be de-chirped by mixing it with a copy of itself, which yields a beat frequency which is much easier to process and is ...
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Converting Clipping stage of guitar pedal to a formula for use in DSP
Been trying to figure out the clipping stage of a tube screamer so i can implement it in a DSP project.
I can simulate a clipping effect by using a tanh(input) type function, which gives me an OK ...
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Help with Project
[Difference Eqution]:
$$LPF_D=\frac{0.1441z^2+0.2881z+0.1441}{z^2-0.6777z+0.254}$$
With a sample of \$T_s = \$ 8e-6 seconds, in scientific E notation.
The difference equation:
\$Y\$ = Output
\$U\$ ...
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STM32F4 DSP noise with inbuilt ADC and DAC
I'm trying to perform signal filtering with STM32F407VGT. I've set up the ADC and DAC to work synchronously, triggered by a timer at 42kHz, and using DMA. The idea is to process half of the buffer ...
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Configuring Frequency Bandwidth and Input Signal for Bandpass filter circuit
How do I set and configure the frequency bandwidth I want the filter to output to a device?
I am using a physical passive bandpass filter which I intend to take the signal in and filter it and output ...
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660
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Wrong FFT result when using rfft function on STM32F4
I'm trying to use rfft function in STM32F407G and I am getting wrong results when I compare it with an online fft calculator . I give a sample input as {1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,...
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Non equal phase currents at nominal speed vector control Permanent magnet synchronous motor
I working on my implementation of vector control for PMSM.
I'm having close loops over speed, current in d axis(flux loop), current in q axis(torque loop). I'm using MATLAB/Simulink for vector control ...
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dsPIC33EP512GP502 -> ADPCM?
It seems that ADPCM is all but non-existant anymore. But I'd like to use this to compress six high-quality audio channels into a smaller bit-stream with little overhead.
There seems to be a dsPIC G....
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149
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RMS calculation of signal with high crest factor up to 10 MHz
I'm attempting to measure the RMS of an AC signal with a crest factor of up to 10, at frequencies of up to 10 MHz. From my brief research I can see many ICs that work well above 100 MHz (designed for ...
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Error while connecting to the target TMS320F2812 with code compser
I am trying to connect to my target:TMS320F2812 the first time after powering up the board,using code composer via JTAG but i am getting this error :
What can i do to fix this?
Please note that :
I ...
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trace32 error "bus error generated by CPU"
I am trying to Boot a DSP TMS320F2812PGFA on his internal SARAM using trace32. The tool detects the processor and i can see it but when i try to run a script, where i initialize the clock and other ...
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DTC Code for TI C2000 Launchpad TMS320F28069M?
Is there some link or resource for code for Direct Torque Control of 3-Phase Induction Motor using the TI C2000 Launchpad TMS320F28069M?
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36
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TMS320F28377S Unable to enter the SCI transmission interrupt
SCI peripheral initialization configuration is as follows:
...
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50
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How to classify filters
I deal with digital signal processing which also deals with filters.
There are 2 main types of filters: Analog and Digital.
To each type there are several classifications such as:FIR/IIR/RCSR(...
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60
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Converting an analog controller into a digital controller... Theory
I have created a stable PI s domain controller for my system. When I go to digitize it in PSIM by adding a ZOH and a delay block and by converting the PI controller into the z domain using backward ...
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2
answers
219
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STM32F446 & External Oscillator
I am currently building an audio guitar pedal. I was suggested to use an external clock as reference for my CODEC and MCU. I've been reading the "Oscillator design guide for STM8AF/AL/S, STM32 ...
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Need help with timing in Verilog functions
I'm doing a filtering project and I'm writing a module that feeds a lot of data to some compute units. There's a lot of really repetitive code and I was wondering if there was any way to condense it, ...
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The effects of frequency resolution in FFT on the frequency spectrum
This is a section for the parameter study of my thesis (basically: why and how I did what I did in the experiments). Currently, I have to choose the fit bandwidth and FFT lines combination for the ...
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215
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FPGA multiplication using DSP hardware, signed vs. unsigned
I'm using the DSP unit (just a fancy name for the multiplier/accumulator unit) of the Gowin GW1N devices to do some fairly simple math. These units accept two 18 bit inputs for the multiplier adding ...
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How do I find the coefficients to know if this color combination is realizable? What am I doing wrong in my solution?
I tried to solve the following problem:
Part A was solved without any problem, however with part B there is a problem:
Second the digital signal processing, to be more specific, image processing, I ...
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1
answer
244
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Incorrect results from DSP48: possibly using 1's complement instead of 2's
I'm using Vivado to write code for an Ultrascale+ FPGA in Verilog and I'm facing an issue with a DSP48. The DSP seems to be outputting the wrong result.
I have manually added a DSP through the IP ...
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1
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44
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External SDRAM with Blackfin and FreeRTOS
I have a custom board with Blackfin DSP and External SDRAM 64 MB and FreeRTOS.
Reading from SDRAM using task with priority 6. In a test I read about 20000 words. Each word is twice consecutively, some ...
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WCDMA , 8PSK signal, 3 G , user end sensitivity, required SNR
Does anyone know how the User End receiver sensitivity for a 3G WCDMA, 8 PSK signal is calculated? and what is the typical SNR required to detect the signal?
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LTE, downlink multiple antenna channel estimation with and without Channel State Information (CSI)
In an LTE downlink with CSI at the transmitter, is the radio Tx in the base station and Rx at the user end hardware part of the channel estimation?
example: Tx to Tx and Rx to Rx isolation between ...
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45
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Double Sideband Suppressed Carrier modulator List
I am using ring modulator for DSB-SC am modulation in a transmitter circuit. Can anyone please tell me about more DSB SC modulator for am modulation? I want to know which one to use where?
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2
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207
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PROGMEM problem with my project - dynamic allocation error
My project is and RTISR (Real Time Instant Signal Recognizer).
I'm sampling a signal from PIN A0 in the Arduino, and I have 6 types of Signals which I compare with (using squared cross correlation to ...
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99
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Filtering Options for an RTL-SDR (DSP and Analog routes)
I have several related questions regarding filtering for an RTL-SDR radio. It's readily swamped by the very, very strong AM and FM radio stations local to me. So much so that your basic passive RC ...
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105
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How to synchronize TI high precision ADC and DAC via SPI?
I am working with DAC80504EVM and ADS8920BEVM-PKD from TI. I am trying to design a system which uses TMDSEVM6657EVM processor board to communicate with these converters via SPI.
However, I am trying ...
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1
answer
60
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Is it possible to digitize small signal with large noise?
I have a small signal, e.g. ~100 uV in a band of interest of 0.1 - 30.0 Hz
This signal is accompnied with a huge noise of 50 Hz ~100V of amplitude.
ADC's input range is 1V.
Is it possible to ...
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How can this problem be solved with partial fractions? (Zero order holder with g(s) block function)
im trying to figure out how to solve this problems for values a=2; actually im stuck, professor told me how to work it, but i cant figure out what to do exactly, we are using partial fractions inverse ...
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Filtering analog audio signal using TLV320AIC3111-EVM
I'm working on a project to filter analog microphone data using the audio codec from TI, the TLV320AIC3111. We are using the EVM However, I'm facing problems with implementing the filters on the ...
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179
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Time delay using IIR filters
I am trying to implement a cardioid pattern with two microphones.
I was reading this paper titled "Digital Filter Array Optimization for Directivity Pattern". The link to download the paper is this. ...
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2
answers
150
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Load vs LDAC pins
Alright, so I'm using a TLV5628 Octal 8 bit DAC with my stm32f4-Nucleo and I'm kind of confused about the difference between LDAC and Load. I am also trying to figure out the clock rate and I might ...
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1
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70
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Can I2S tdm interface send more channels with less sampling frequency?
We have a arm SoC(system on chip) connected with I2S to a DSP (digital signal processor). SoC and DSP both support 48khz, 8 channel and 16bits in TDM mode.
Is it possible to use this interface to ...
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339
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How to change step pulses into PWM pulse synchronously?
I am driving a stepper motor using microstepping techniques.
For the input signals to the driver, step and dir are used.
More than 100,000 steps/second speed is target.
The PWM frequency is below ...
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1
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DSP board TMDX5505EZDSP potentiometers and switches
I have to do a project for school that is an audio effects processor but I'm not experienced with dsp. I'm using the Texas Instruments TMDX5505EZDSP. I've programmed some audio effects based on some ...
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149
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FIR Filter delay calculation for cascaded filters
I have created a simulink model which had two filters implemented with an FIR block cascaded in series.
The first filter in my case is a moving average filter and the second one a Gaussian filter(...
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1
answer
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Need to mix an audio signal from a low power device, into a high power speaker
Basically, I want to take a cable going from the car audio amplifier to a speaker which is sending around 50W of power, that cable, and put a mixer in there, where I will inject an audio signal that I ...