Ben Wild and Josh Reynolds by yTLGz9

VIEWS: 0 PAGES: 3

									                                                                                  Steve Holstein and J.R. Allen

                                    ECE 345 Project Proposal

Introduction
         Each of us developed the idea for the project independently and found surprising
similarities in the functionality when we talked about our ideas. We are both eager to
develop this project for the challenging experience of creating something new as well as
the marketability we foresee of a working design. This project will at the same time
allow us to demonstrate for ourselves the ability to adapt to projects since neither of us
are experts on RF communications.
         By the completion of our project, we hope to have a unit which will communicate
with other similar units automatically. A centralized website will coordinate the function
of the units by providing software to reprogram the units as well as allowing users to
lookup websites managed by the sender. The units will interchange a string and a unit id.
The string’s function will be to entice receivers to lookup the sender’s website by typing
in the sender’s unit id at the centralized website. In order to control overloading of the
unit, we hope to implement a class system for messages, so that messages may be filtered
out, i.e. a person at a convention looking for software could filter out all hardware related
messages.
         In maintaining a centralized website which the units depend upon, we add
additional marketability to the project by providing a high trafficked area of users seeking
specific information which can be used to provide additional advertisements from related
groups. While the project is specifically aimed at business conventions, it is our belief
that the units could become popular for everyone as a way to meet new people and
receive focused advertising.
                          Buttons: Next, Last,
                          Delete
                                                                  MODEM: FSK


                                                 CPU




                                                       ROM: UNIT ID,
                          Display                      PROGRAMMING

                                                       RAM: String, additional
                                                       programming, Stored Messages



The buttons are used to control the unit allowing to go forward and backwards through
the messages and delete old messages. The display shows the contents of the message
and the unit id of the sender, along with any navigational messages to assist the user if
needed. The ROM contains the unit id which identifies the user of the unit, along with
the essential programming information. The RAM contains the unit’s programmed
string, the additional programming supplied by an update from the central website, and
all the stored messages logged on the unit. The modem controls the interaction of the
units by supplying a common channel which units compete upon to deliver their message
to other units. The CPU provides the control for the device, managing the
communications protocol when in idle, and displaying the messages in response to user
input.
        The communications protocol will be similar to that of ethernet, where all devices
wishing to send compete for the channel, setting a random exponential delay each time
they are blocked from the channel, until finally only one device gains access to transmit.

Performance Required
         The basic level of performance will be to interchange the pages from multiple
units. Once this is accomplished, measurements will have to be taken in order to
determine the proper delay settings to ensure efficient use of the communication channel.
A well tuned device should be able to interchange messages with no more than a half
minute delay for each device added.
         The range of the device will intentionally be kept small in order to limit the
number of units competing in the same area. We assume that the people carrying the
units will move around and therefore the units will be able to compete with all other units
in a finite amount of time. Therefore a good performing range will be maintained to a 40
ft. radius.

Quantification
        Once the message has been successfully sent. The unit’s message length will be
adjusted to achieve a balance of string size to transmission time. This data will be
tabulated on a graph and used to set the delay for the device. The delay for the device
will use the data from the graph of message length vs. transmission time to simulate
channel competition on a computer. The random delay will be tuned by the simulation to
find a maximum of throughput with a minimum of competition delays. This data will
also be tabulated in graphic format to illustrate the role of channel competition in device
functionality.
        The range for transmission will be tabulated by recording transmission times vs.
distance between units and the output power of each unit trimmed to 40ft.

Schedule

 Date                               Items to be Completed
2/14/00       Receive parts, read technical documents, design RF section of unit
        Discuss RF section of unit and the communications protocol, design the CPU to
2/18/00
                                          RF interface
2/21/00    Programming; communications protocol, menu system, serial download
2/25/00                                 debugging and testing.

2/28/00                                 Debugging and testing

 3/2/00            Simulation coding to achieve optimal exponential backoff delay

 2/6/00                                 Debugging and testing
Cost
—Labor
     $30/hour x 2.5 x 100 hours/person x 2 people =           $15,000

—Parts
         2 Motorola HC08GP20 8-bit microcontrollers          $20
         2 2-line LCD displays                               $10
         2 FSK modems
         6 pushbuttons                                       $10
          Various op-amps, resistors, capacitors,
                 wires, ribbon cables, sockets,
                 and transistors                              $40
         Total:                                               $80

TOTAL:                                                    $15,080

Engineering Specifications Test
        We will test the resistors in the output section extensively to limit transmit power
to the appropriate range.

								
To top