WVU Returns to RockSat 2010: A Research and Education Project West Virginia University Rocketeers Student team: N. Barnett, R. Baylor, L. Bowman, M. Gramlich, C. Griffith, S. Majstorovic, D. Parks, B. Pitzer, K. Tewey, E. Wolfe Faculty advisors: Y. Gu, D.J. Pisano, D. Vassiliadis June 2010

– The mission of WVU RockSat is to design, build, and test three atmospheric and plasma physics experiments: a temperature measurement, a vector magnetic field probe, and a radio-sounding plasma-density measurement. We expect to obtain height profiles for the first two experiments and get a proof of concept for a novel plasma measurement. Mission Statement

Mission Overview: Radio Board Measured variable: plasma density. Processes: solar UV produces ionosphere >85 km. Objectives: – Emit radio pulse which is reflected where index of refraction=0 – Measure density profile; identify E layer peak – For high-activity conditions: high-density patches descend to E-layer altitudes (“spread-F” effect)

Mission Overview: Main Board Measured variable: temperature. Processes: atmosphere heating/cooling mechanisms. Objective: identify layers based on temperature profile Measured variable: terrestrial magnetic field. Processes: field controls charged-particle motion. Objectives: – Measure vector B, dependence on latitude, geocentric distance. – For high S/N: detect low-frequency waves

Mission Research Magnetic field: – Strongly involved in plasma structure and dynamics. – Experiment measures power-law decrease of field magnitude with geocentric distance. – differences in Earth's magnetic field can be caused by the interaction between charged particles from the Sun and the magnetosphere of a planet

6 WVU Functional Block Diagram Main Board Power flow Comm/Con Data flow Legend Power/Reg Comp/Store Sensors Power Supply Thermistor uMag X/Y/Z G uController Flash Memory RBF Z Accel Gyro X/Y ADCADC Inertial Sensor Reg DIGITALDIGITAL Geiger Counter Mag X/Y/Z P/Q/R Ax/Ay/Az Temperature Battery

uProcessor: Netburner MOD5213 Programming Language: C++ Programming Requirements: Periodic Interrupt Timers (PIT) 8 Analog to Digital Pins Serial Peripheral Interface (SPI) 5 Digital GPIO Pins Write 19 sensor channels to binary text file Write to external storage using a serial port additional serial port for uploading software

Main Board PCB Vertical Breakout Board

Geiger Counter Included a Geiger counter in payload to help verify Plasma Density experiment

WVU in RockSat 2010: Functional Block Diagram 10 Power Supply Swept-f Pulse Tx Radio Board Fixed-f Pulse Tx Pre-amp & Power filter Super het LO Amplifier IF G Regs ANT RF in uController ADCADC Flash Memory ANT RF out

Transmitter Schematic

Latest testing Transmitter works on PCB when high-resonance frequency (>2 MHz) inductors are used. If in addition, inductances are high, then we can use low capacitances.

Receiver Schematic

14 Programmable Circuit Elements Programmable Capacitor used to control Transmitting and receiving frequencies The Mod5213 PIT is used to control the digital capacitor (Max 1474) We control simultaneously multiple capacitors: useful in extending range or resolution of effective capacitance

Final Payload

Concluding Remarks Constructing our RockSat payload was a great hands on learning experience for experimental design and build. WVU looks forward to participating in the next RockSat.