Soil Moisture Radar – Ongo-02d ABSTRACT During times of increased flood problems, soil moisture becomes a paramount concern among geologists due to the direct relationship between the moisture content in soil and floods. One of the common ways to determine soil moisture content is to take an actual sample to the lab and test it, which is a very time consuming task. The focus of this team is to use a ground-penetrating radar (GPR) capable of measuring soil moisture content. This radar device, called SOMORA (SOil MOisture RAdar) encompasses both a transmitter and a receiver. The transmitter directs an electromagnetic radar pulse toward a section of soil by use of an antenna. This pulse reflects off the soil, and a portion of this reflected pulse scatters towards the receiver through an antenna. By measuring the strength of the scattered signal, the soil moisture will be determined. This method is time and cost efficient compared to the other available options. PROBLEM STATEMENT The current technology used to predict floods is slow and labor intensive. SOMORA will predict floods more efficiently using computers. OPERATING ENVIRONMENT The end product will be installed in an airplane or a weather balloon and subjected to the following conditions. Vibrations Extreme temperatures Rain and moisture INTENDED USERS Meteorologists Flood prediction centers Farmers INTENDED USES Measure moisture content of soil Predict floods ASSUMPTIONS Strength of received signal is proportional to the moisture of the soil Power supply can provide enough power to run all parts of the radar Outside signals will not interfere with the transmitted signal Soil moisture content can be extracted from the received pulse LIMITATIONS Must weigh less than 25 pounds Volume must be less than three cubic feet Must cost less than $1500 EXPECTED END PRODUCT AND OTHER DELIVERABLES SOMORA will be battery operated and capable of detecting moisture levels in soil. The radar will consist of an analog system and digital system. The analog system will be comprised of a transmitter and a receiver. The digital system will consist of an A/D converter and a microcontroller to process the signal and send it to a computer for analyzing. DESIGN OBJECTIVES Analog Team: Install new equipment (LPFs, VCO, mixer) Integrate the analog and digital systems Perform power tests Digital Team: Incorporate ensemble averaging program to FPGA Synchronize the A/D to derive soil moisture content FUNCTIONAL REQUIREMENTS Transmit and receive signals using single antenna Reduce noise in the signal Store data in an on-board memory device Interface with a PC to interpret data DESIGN CONSTRAINTS Radar must transmit and receive signals accurately Size is limited to 25 lbs Low power consumption to minimize battery size Sturdy design RADAR SYSTEM MEASURABLE MILESTONES Low frequency VCO, mixer, and LPFs installed Ensemble averaging program installed to FPGA Analog and digital systems completely integrated PROPOSED APPROACH Perform A/D converter simulations Analyze receiver noise gain Test radar components independently Perform circuit analysis PERSONNEL EFFORTS OTHER RESOURCES Advanced Design System (ADS) MAXPLUS CLOSING SUMMARY Satellites can not accurately detect moisture content because their spatial resolution is not as high as low altitude radar. A low altitude Ground Penetrating Radar (GPR) can be used to measure the moisture content of soil. Radar reflects off the soil, and a portion of the reflected pulse is picked up by the radar receiver. The amplitude and wave shape of the reflected pulse is used to determine the moisture content of the soil. Introductory Materials Project Requirements Contact Information: Iowa State University Spacecraft Systems and Operations Laboratory 2362 Howe Hall, Ames, IA Client: Iowa Space Grant Consortium Advisor: Dr. John P. Basart 2 nd Semester Team Members: Navpreet RandhawaCprE Oneza SohelCprE Shannon WannerEE Phil LehtolaEE Adeel MankeeEE 1 st Semester Team Members: Ahmed GamalCprE Barani NaiduCprE Jonathan BensonEE Abram HardingeEE Proposed Approach and Considerations TECHNOLOGIES CONSIDERATIONS Pulse Generator A/D converter Field Programmable Gate Array (FPGA) Basic electrical components TESTING CONSIDERATIONS Independent component testing Full system testing Program testing Estimated Resources and Schedule FINANCIAL RESOURCES PROJECT SCHEDULE