1. ENEE 498c---Fall 2003 Project Description: RF Range Finder

2. System Description Function –Measure the distance between two identical units. –Two operation modes: “Measure” (M) and “Broadcast” (B) –An unique code for each unit; the M unit can be set to look for a specific B unit. Specifications –1 m resolution –255 m range 1 m ≡ 3.3 nsec (3.3e-9 sec*3e8 m/sec≈1 m) => clock frequency=1/3.3 nsec=300 MHz 255 m ≡ 8 bits, binary: 8-bit counter

3. System Description: Block Diagram Control parameters: Unit’s self ID Target unit ID if in M mode Seeker unit ID if in B mode Operation mode Calculator: The PIC16F62XPIC16F62X Distance indicator: 7-segment display

4. System Description: Logic Design Signals present on the board: - B / M: “broadcast / measure”. B’=M - TE: “transmit enable” - TRV: “transmission received valid” - S : “send” (for unit in M mode) - C / CS: “count / count stop” TE = (BTRV) + (MS) CS = MTRV C = MS

5. System Description: Timing S C TE M RF to airRF receivedTRV B ↑ TE B RF to airRF received TRV M ↑ CS Board delay RX/TX chip and antenna delay Distance delay: Valid for measurement Calibration required: Build-in a delay subtraction after calibration measurements.

6. RF Components Transmitter: LINX RXD-433-KH –Relevant features: –TE “Transmission Enable” pin –Address pins to give unit unique ID code Receiver: LINX TXE-433-KH –TRV: “Valid transmission received” pin –Address pins to set the code of the unit to “listen” for Antenna: LINX planar antennas On-board integration information: Available in application notes