Communication Project: Part 1 - (Introduction)
So...I like digital communications and have been wanting to get into radios and antennas. Ever since I took a course three semesters ago,in digital communication. It fascinated me as to how humanity has designed systems that allow you to do amazing things such as make phone calls from halfway across the world with a device in your pocket. Moreover, this device cannot only make calls to another geographical place in the world, but can stream videos, search the web, upload data to websites, and much more using digital communication, namely wirelessly. Therefore I have set out to understand more about the field and begin a career within the communication field (please hire me :) ). In doing so, I have begun tutoring for digital communication, taken a course in wireless communication and worked an internship at a communication company. So, I thought to myself with all the knowledge I have amassed, I should begin constructing a project of my own that will continue my personal understanding of communications. And while in the process I thought to myself, what is the most basic form of communication that men(and woman) have used for years and years... the radio. Hmmmm... a radio sounds like a good idea, yet a radio comes with a lot of its own design concerns... such as the fact that its a predominantly ANALOG circuit. When I say analog I mean hard... I mean the true definition of analog is a continuous electrical signal, versus in the digital world where digital indicates a discrete electrical signal. While I have nothing agaisnt analog guys, I personally as a computer engineer have very litte experience with analog circuits (thanks college of engineering for not making me take electronics/circuits2). However, I have not let anything set me back as of yet, and I won't begin now. So I thought to myself, and I remebered that during my internship I learned about a technology that emerged in radio design within the 1900's (probably), called a Software Defined Radio - SDR for short. While the discussion of a SDR is quite a bit more complex than the scope of this post, I will say for now that the SDR essentially allows for parts of the radio to be controlled or done in the "digital" domain - through software - versus the traditional approach which would have been through analog means. Well this is great because I can "do" software, thats pratically what I have spent a large portion of my collegiate career learning about. Therefore, I know that to help offset my knowledge of analog circutry, I can develop the radio using an SDR and then learn along the way about the analog circutry. Given that a SDR will be developed, I first had to understand a few things. First... what is an SDR developed on? This question while may seem confusing at first (for those unaware of the choices), yet clear to those who work with varying software platforms. An SDR can be developed on many things but traditionally, it is done on an FPGA/ASIC. An FPGA or Field Programmable Gate Array is a device that has "logic" gates and can be used to program what we call boolean algebra. For a greater understanding of what this is... click boolean algebra and enjoy. Moving on from there the reason an FPGA is chosen as the device to program an SDR on is first, it provides quite a bit of flexibility to the user in the implementation and secondly (the BIG ONE), you can implement complex signal processing algorithms on an FPGA fairly easily. Easily being because A. You are a Genuis at VHDL/Verilog and can program algorithms easily or B. You wrote an algorithm in MATLAB and used MATLABs' translator to VHDL/Verilog. I am personally more of the B variety, however I'm working on the A variety. Anyways I digress, now that we understand more about why an FPGA is chosen, we have to understand what we are doing with the implemented device to make this "SDR radio" and that will be covered in the first section of this series. Thanks for reading and be on the lookout for more information!