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In this project you are asked to analyze and design an ACLR filter. These filters normally referred to as pulse shaping filters are used at the last stage of the baseband processing in a communication system. The purpose of this filter are many folds but the key goal for having this filter is to make sure that the information for a certain user does not leak to the next adjacent channel. An adjacent channel in this case is the user that is occupying the same bandwidth next to user 1. Government agencies setup rules so that interference from one user to the next user is minimized.
For this design you need to consider an FIR filter. The normal implementation is a linear phase FIR filter. You will need to design two filters at two different sampling rates.
Design of ACLR filters for a 2.5GHz Radio
In this project you are asked to analyze and design an ACLR filter. These filters normally referred to as pulse shaping filters are used at the last stage of the baseband processing in a communication system. The purpose of this filter are many folds but the key goal for having this filter is to make sure that the information for a certain user does not leak to the next adjacent channel. An adjacent channel in this case is the user that is occupying the same bandwidth next to user 1. Government agencies setup rules so that interference from one user to the next user is minimized.
For this design you need to consider an FIR filter. The normal implementation is a linear phase FIR filter. You will need to design two filters at two different sampling rates.
Specifications for both filters are as follows:
Step 1:
• Sampling rate = 61.44 MHz
• Stopband attenuation <= -45
• Stopband edge = 1 MHz from the corner frequency
• Corner frequency w.r.t. center frequency = 9 MHz
• Channel BW = 20 MHz
• Adjacent channel = 20 MHz on each side
Step 2:
1. Design a source signal with at least 10 frequencies between 0 to 10 MHz on each side. Add a noise signal to the source so that the overall signal to noise ratio (SNR) is equal to 10 dB.
2. Clip the signal by a variable level (make the peak to average ratio starting value of 8 and then 7dB).
3. Plot the FFT magnitude of the signal before and after clipping.
4. Pass your clipped signal through the filter you designed in the first step. Make sure that the clipping level is enough so that without filtering the ACLR requirement is violated.
Your report should have the following sections:
1. A general write up on ACLR filters and why and where they are used what types are commonly used.
2. Rewrite the specification and choose a filter structure for implementation.
3. Analyze the filters (draw the pole/zero location and show the frequency response and the linear phase property).
4. Show your results that the specifications are met by plots etc.
5. Write a conclusion of your analysis.
6. Include your MATLAB code for doing all the analysis.
7. Send a soft copy of your report and your code to my email address by the due date. Make sure that your report and MATLAB files are all in a single zipped file with your name and student ID as the file name. The file you sent should look something like this but instead of my name you should use your own name: EE450FinalProject_ali_pirooz_stID1111.zip
1.Adjacent-channel interference (ACI) is interference caused by more power from a signal in an adjacent channel. The ACI which receiver A experiences from a transmitter B is the sum of the power that B emits into A's channel known as the "unwanted emission", and represented by the ACLR (Adjacent Channel Leakage Ratio) or It is the ratio of transmitted power to the measured power of a receiver filter in the opposite RF channel. Previously, ACLR was called Adjacent Channel Power Ratio. ACLR is a term that came into use in standardization of the UMTS(WCDMA) standard by 3GPP.
ACLR defined for two cases in UE case:
•E –UTRA (LTE) ACLR1 with rectangular measurement filter
•UTRA (W-CDMA) ACLR1 and ACLR 2 with 3.84 MHz RRC measurement filter with
roll-off factor α =0.22.
2.specifications:
Adjacent limit.
Alternate limit.
Manual power range offset.
Measurement timeout.
Multi-measurement count.
Trigger arm.
Trigger source.
Trigger delay.
Time slot to measure.