1.2 Implementation of a Demodulator

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1.2 Implementation of a Demodulator

• Sponsor Steve Hicks, FlexRadio Systems
• Faculty Advisor Dr. Harold Stern Dr. Semih
  Aslan

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Team Members
Jonathan Rodriguez Project Manager Software
Designer
Cory Cox Software Designer Test Engineer
Nicolas Govea Software Designer Validation
Engineer
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Todays Presentation Covers

• Motivation
• Description of Project
• Team Roles and Responsibilities
• Project Progress
• Plans for the 2nd semester

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Roles and Responsibilities

• Project Manager Jonathan Rodriguez
• Managerial Duties
• Schedule team meetings
• Communicate project progress with the project
  sponsor and the instructor
• Monitor projects milestones
• Research
• Software defined radios
• Error handling
• Constraints
• Software design
• Configuration between devices used

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Motivation

• The Problem
• Analog and digital radio operators currently can
  not communicated with each other due to
  incompatibility of communication
• The Solution
• By implementing System Fusion, the radio will
  automatically switch the transmit mode from
  either digital or analog based on the mode
  detected by the receiver.
• Why is this important?
• With the ever growing digital world, System
  Fusion Fusion bridges the gap between the analog
  past and the digital future

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Sponsored by FlexRadio Systems

• Why FlexRadio Systems?
• FlexRadio currently does not have communication
  modes that support interoperability between
  analog and digital
• Yeasu has developed System Fusion, with C4FM as
  the standard modulation technique, which solves
  this problem
• With addition of System Fusion into their radios,
  FlexRadio can meet consumer demands of having
  many communication modes in one product
• This allows FlexRadio to continue to be the
  industry leader in software defined radios

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What is System Fusion and C4FM?

• System Fusion
• Four different communication modes
• Full Rate Voice Mode
• Full Rate Data Mode
• Voice / Data Mode
• Analog FM Mode
• Continuous 4-Level Frequency Modulation (C4FM)
• The standard modulation scheme used for System
  Fusion

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Project overview

• Goals of Project

• Stretch Goals of Project

• Successfully code and implement the digital
  modulation scheme C4FM.
• implement the full rate voice mode of System
  Fusion
• Integrate the modulation scheme and voice mode
  into FlexRadios SmartSDR software.

• Successfully implement the other modes of System
  Fusion
• full rate data mode
• Voice/Data mode
• Analog FM mode

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Roles and Responsibilities

• Team Member Nicolas Govea
• Research
• Boundary conditions
• Use cases
• Characteristics of C4FM
• Performance
• Software design
• Demodulator
• Validation Engineer

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General Signal Process

• System level diagram of the implementation of
  C4FM.
• Everything inside the red dotted line will be
  designed and coded for this project.

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C4Fm Characteristics
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Project Elements

• Modulator / Demodulator
• All code written in c language
• Eclipse compiler
• GitHub repository

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• Why this is a good Senior Design Project

• Implementing C4FM Modulation Scheme
• Insight as to how signals are transmitted via
  communication devices.
• Gain programming skills through the
  implementation of a digital modulation scheme.
• Insight into the design process and how real
  world companies operate.
• This project allows us to expand our skill set,
  in a way that can not be achieved in classroom
  settings

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Major Milestones

• Intermediate Design Review November 20, 2015
• First Semester Report Presentation December
  2, 2015
• Test Plan February 15, 2016
• Characterization Report April 4, 2016
• Final Design Review April 15, 2016
• Final Semester Report Presentation - May 3,
  2016

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Project Deliverables

• Tasks to be delivered
• Setup communication between devices
• Write code for C4FM modulation scheme
• Implement modulation code into SmartSDR software
• Write code for C4FM demodulation scheme
• Implement demodulation code into SmartSDR
  software
• Live test system for voice mode

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Roles and Responsibilities

• Team Member Cory Cox
• Research
• Interfacing
• System requirements
• Existing systems
• Performance
• Software design
• Modulator
• Test Engineer

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Constraints

• Budgetary
• FLEX-6700
• STI-CS Speech Intelligibility Meter
• Design
• FlexRadio Signature Series radio
• SmartSDR Software
• Writing in C language
• Maintainability
• GitHub repository

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Standards

• System Fusion
• Allows for automatic mode select
• C4FM modulation scheme
• Faster transmission rate
• Larger bandwidth
• FLEX Signature Series Radios
• Code will be unique to operate with SmartSDR
  software

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Challenges Concerns

• Limited resources for examples of C4FM
  implementation
• Currently only one company implements C4FM scheme
• Configuring our code into FlexRadios SmartSDR
  software
• Access to VHF compatible radio
• Budget limitations for testing intelligibility of
  speech output
• Robustness of our System

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Project Progress

• Research completed for
• Software defined radios
• System Fusion
• C4FM modulation
• Symbol mapping
• Error control handling
• Performance
• Parts procured
• FLEX-6300 series radio
• ThumbDV DV3000U dongle

FLEX-6300 SDR
ThumbDV
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2nd Semester Tasks

• Tasks Planned for the Completion of the project
• Configure ThumbDV dongle to computer / radio
• Write code for modulator / demodulator
• Implement code into FlexRadio SmartSDR software
• Test modulation and demodulation performance
• Perform live voice test over radios

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Hamming it out