DTMF DECODING
Project - EECE323 School of Engineering American University in Dubai
Course: EECE323–Fundamentals of Digital Signal Processing
Semester: Spring 2021 Instructor: Dr. Khaled Ali
Due Date: 10 April, 2020 @ 11:59 pm
Submission Guidelines:
• Your submission should be emailed to kali@aud.edu • Failure to abide with submission guidelines will result in deduction of marks. • Submissions later than 10 April, 2020 @ 11:59 pm will not be accepted. • Marks will be deducted for lack of neatness or organization. • An oral exam composed of a set of questions regarding the project will be administered
after submission.
– Your mark on the project will be weighted by your performance on the oral exam.
– The oral exam will be conducted on MS Teams, with the camera on.
– The date and time of the oral exam will be assigned to you at a later time.
• Groups of two or three can be formed; however, all members are equally responsible for the entire submitted work.
– The oral exam for each student will cover the entire project.
– For groups of three the research component has to be done.
• Save your file as follows: Project-EECE323-NameStudent1-NameStudent2.zip – if you are submitting more than one file (eg: MATLAB file and pdf file), combine
all your files in a single “.zip” file and save it according to the aforementioned naming conventions.
* By signing above you confirm that the submission has been fully prepared by you. Any suspi- cion of copying or plagiarism in this work will be reported to the Dean or Chair for appropriate investigation and appropriate disciplinary actions, which may result in a “0” on the work, an “F” in the course or other penalties as described in the Student Handbook, which can be found online at: http://www.aud.edu/files/StudentHandbook.pdf
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EECE323–Fundamentals of Digital Signal Processing Spring 2021
Dual-tone multi-frequency (DTMF) signals are the tones (sinusoidal signals) generated by a tele- phone keypad. Each digit on the keypad is coded to a signal that is composed of two sinusoids, based on Table 1.
Table 1: DTMF Tones
1336 Hz 1209 Hz 1477Hz 697 Hz 1 4 7 852 Hz 2 5 8 770 Hz 3 6 9
For instance, once the button for digit “1” is pressed, the signal sin(2π1336t) + sin(2π697t) is generated by the phone, where the signal duration is 0.5 seconds. At the decoder, each digit is identified based on the same pre-defined tone combination.
One important application of DMTF is private branch exchange (PBX), which is a private tele- phone network used within an organization. In PBX systems, each telephone line connected to the PBX is assigned an extension number. Someone who dials the organization’s number, once connected, is asked to enter the desired extension number of a specific party. Based on the keyed extension number (input signal), the call is routed to the appropriate telephone line within the organization.
The objective of this project is to design a DTMF decoder, which is capable of decoding a four- digit extension number. Note that a four-digit extension number is composed of four consecutive DMTF tones based on Table 1.
Twenty signals are uploaded to blackboard. Signals “TestSignal No1 ” to “TestSignal No10 ” are noiseless signals, while signal “TestSignal No11 ” to “TestSignal No20 ” are noisy signals. All signals are sampled with 8 kHz sampling frequency. Note: in MATLAB, you can sound any of the test signals using the “play” function.
In this project, each group will design and implement a DTMF decoder in MATLAB/Simulink. The decoder should be able to decode any four-digit extension number generated from Table 1, whether noisy or noiseless. Thus, the input to the decoder should be any of the test signal (or any signal generated based on Table 1), and the output should be the corresponding four-digit extension number.
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EECE323–Fundamentals of Digital Signal Processing Spring 2021
For Groups of Three: Research Component
The objective of this component is to research and study applications of digital signal processing (DSP) in emerging and modern technologies.
For this component, each group should conduct a literature survey to understand the impact of DSP has on our lives. DSP has many applications in many fields, such as audio and speech processing, radar and other sensor array processing, telecommunications, digital image processing, bio-medical engineering, among others.
Write a 1500 word research essay addressing the following criteria:
1. Applications of DSP in the various fields.
2. Emerging and modern technologies in one of the many fields where DSP is utilized.
What to submit?
Along with the project report submit your SIMULINK/MATLAB files (commented and com- pressed into one file)
The project report should include:
• Brief discussion on the reasoning behind your design. Include a block diagram of your decoder.
• A table identifying the extension number of atleast 5 noisless signals and 5 noisy signals. • Screenshots of any Simulink block diagram • All MATLAB code, properly documented and attached as an a appendix
Note:
1. The report should follow a standard report structure (i.e. introduction, discussion, conclu- sion,...etc), with table of contents and list of figures.
• Use Times New Romans 12 pt, double space • Submit both a pdf and a doc version of your report. • All your references should be cited following the IEEE citation style.
2. Follow the submission guidelines, including the naming convention, on the cover page.
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