Download a copy of Lab3 MA FIR.zip from the course shell onto the desktop of your computer and unzip the project to the desktop. Double click on MA FIR.mcp to open the project with CodeWarrior, and then load it into the Tower system. Compile, load, and run the program on the Tower system before proceeding to the next step. This loads and runs the 9-point, moving average filter using the input ADC and output DAC channels that you have just connected. With the moving average filter program running on the Tower system, verify that the output shown on Channel 1 of the oscilloscope is a sine wave and that the frequency is the same as the input signal from the signal generator. Open a new Excel spreadsheet, and create a data entry table similar to what is shown in Table 2. Measure and record the filter output amplitude for the Vin = 2.0 Vpp at 10 Hz. Record this measurement as the 0 Hz measurement due to filter restraints. Without changing any other settings, increase the frequency to 50 Hz, and record this measurement as the 50 Hz measurement. Increase the frequency by 50 Hz to 100 Hz, measure and record the filter output amplitude for the Vin = 2.0 Vpp at 100 Hz.
9/18/2018 Week 3: Lab Overview: Signal Processing with Lab - 11065 12/14 Repeat the above steps for all frequencies listed in Table 2 increments of 50 Hz up to and including 1,000 Hz. 9-Point, Moving Average Filter Frequency Response Linear Vin = 2.0 Vpp Freq (Hz) Vout (p-p) Note: 10 Hz used for 0 Hz 0 Measurement 50 100 150 200 250 300 350 400 450 500 550 600 650 700
9/18/2018 Week 3: Lab Overview: Signal Processing with Lab - 11065 13/14 750 800 850 900 950 1,000 Table 2: Data Table for Moving Average Filter ResponseCopy and paste your moving average filter response Excel data table into the Week 3 Lab coverreport in the space provided.From the data recorded in the previous steps, create a graph of the 9-point, moving average filterlinear magnitude frequency response, similar to what was shown in Figure 3. Copy and paste thisgraph into the Week 3 Lab cover report. This graph will be used to answer several questions inthe cover report.Please note that because you have just measured a 9-point, moving average filter, that the graphwill be somewhat different than the 7-point, moving average filter shown in Figure 1. However, thefollowing calculations and frequency points are still accurate.The first zero gain (linear) frequency point occurs at 2π/M or F /M, where F is thesampling frequency of the system.The cutoff frequency, where the gain of the filter drops to 0.707 of its DC value, occurs atπ/M or 0.5F /M, again where F is the sampling frequency of the system.Answer the following questions in the Week 3 Lab cover report.Sallen-Key Low-Pass Filter Analysis QuestionsUsing the Vpp output at 1,000 Hz as your reference, and the fact that a second order, low-passfilter attenuates a frequency at the rate of -12 dB per octave, calculate the dB attenuation perdecade for the measurements indicated below.
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- Fall '15
- Digital Signal Processing, Low-pass filter, Finite impulse response, Electronic filter, Digital filter, Lab Overview