- Create Documentation for user requirements, design calculations, sequence diagrams, activity diagrams, etc.
- Simulate a 1-D chirp pulse transmission and reception
- Build and test 1-D sonar
- Simulate 2-D sonar with fan beam image
- Build and test 2-D sonar imaging sysem.
- chirp_gen.ipynb used to generate array of values in chirp (int values pre-adjusted for DAC)
- globals.h contains chirp array
- Chirp_Output.ino produces chirp using teensy 3.6 DAC0.
- LibSerialPort.ipynb to receive buffer from Teensy through serial port
- Sampling.ino samples using ADC on teensy.
one transmitter and one receiving transducer.
requires that a narrow beam is steered over a range of angles to form a fan-beam image. Steering can be implemented electronically by using a linear array of transducers, either for the transmitter beam or the receiver beam. By combining the received signals with appropriate delays, beam steering can be achieved.
can be implemented in different ways. A simple method is to use two perpendicular arrays, one for steering a transmit beam, and the other for steering a receive beam. This achieves 3D imaging with a minimum number of channels (compared to a conventional NxN receiving array).
Radar/sonar transmits a chirp pulse (wide bandwidth for fine resolution; long in
duration for high energy. Received signal is passed through a matched filter.
Output waveform has improved peak SNR. Below is shown a simulation of one
echo.