ELEC 432

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Background

A stroll down the aisles of Circuit City, Best Buy, Fry's, Micro Center, or any other technophile supermarket will quickly reveal a nearly endless assortment of convenient, pocket sized wireless gadgets. Any device offering a new (though previously unheard of) function suddenly becomes essential, necessitating its immediate purchase. Unfortunately, keeping up with this ever expanding list of necessities results in an ever expanding pile of gadgets.

Just as important as functions that you can buy are those that you can create yourself. As a graduate of ELEC 432 you will have the skills to quickly design and construct any clever wireless gadget that comes to mind. But once again building each one from scratch results in an unwieldly pile of gadgets.

The problem of clutter and cost would be greatly reduced if one could buy a generic wireless gadget which, by downloading a bit of software and perhaps installing a small (and inexpensive) module, could instantly be transformed into any (or perhaps several at once) of the gadgets mentioned above. This is a job for the Universal Radio Product.

Description

This device has two primary goals. One is to allow a user to utilize a number of existing radio based services without having to carry around the same number of separate boxes. The other is to facilitate the design and realization of new radio based applications. It will consist of (1) a base unit containing components required for all applications (power, display, input, audio, data/signal processing, etc.), (2) modules to provide additional hardware functionality as required, and (3) software to enable individual applications.

Specifications

Size and Shape

Your system should be as close to pocket sized as possible. A good target would be 5" x 2.5" x 1" for the base unit with battery and at least two modules. Some functions (e.g. RC transmitter) may require add ons or accessories that significantly increase the size when that functions is being performed. Such accessories should be easy to install and remove.

Cost

Although the initial cost may be higher than many of the gadgets it replaces, incremental cost of adding additional functions should be low enough that a system performing 3 or 4 functions would be cheaper than the total cost of an equivalent set of stand alone units.

Supported Applications

Your system should be capable of implementing all of the following applications (and many others as well). Your prototype should realize at least 2 of these plus one additional new (i.e. currently unavailable) application of your own choosing. To the extent physically possible you should be able to employ all applications simultaneously.

• FM radio (including RDS)
• NTSC video (at 2.4 GHz, for use with wireless cameras)
• Airband scanner
• NOAA weather radio
• RC transmitter for model car, plane, helicopter, etc.
• QRP ham station
• Wireless Mouse/Presenter
• GPS

Platform

The basic shape of this project is a big box into which a number of smaller boxes may be plugged. There are several possible choices for the big box:

• Custom design. The greatest flexibility is provided by designing the entire system as a single, coordinated entity. Unfortunately, this also provides a greater amount of work. However, it is possible that effort invested in the design of the core and interconnections can reduce the effort required for each additional module.
• The BUG. One attractive candidate for the base unit is The BUG. This is a pocket sized system built around a core module containing an ARM1136JF-S-based microprocessor with 128 MB of memory, rechargeable lithium-ion battery, USB, Ethernet, MMC and serial interfaces, and a small LCD with button controls. It runs the Linux operating system and supports up to four snap-on expansion modules.
• PDA/Smartphone. Adding radio functions to a smart phone seems like bringing coals to Newcastle. In fact manufacturers are only likely to provide functions that phone companies can charge you for. A more significant concern is the physical environment: the size constraint of standard PDA/smartphone expansion options is severe. More space would be available with some kind of docking adapter or via extensive case modifications, but this introduces significant mechanical and esthetic challenges.
• Asus Eee PC. Although not realy pocket sized, this sub-laptop PC is still fairly portable. Priced about the same as the BUG, it offers more performance in exchange for less compactness. Although conventional expandability is limited to USB, hardware hackers have already done a number of things the manufacturer never intended ( here's an especially ambitious example) so a more integrated product is possible.