Introduction
Two-dimensional bathymetric surveys are conducted using an Odom HT100 survey-grade singlebeam sonar system. The system is compensated for motion with a TSS DMS-10 MRU and uses a Trimble 5700 low latency, real-time kinematic GPS for precise positioning, supplemental heave measurements and tidal offsets. Accurate depth information can be collected in less than 0.25 m of water when coupled with the Surfzone Explorer or mobilized on a larger vessel for extended operations.

Singlebeam Sonar Mount for Surfzone Explorer	Singlebeam Sonar on Surfzone Explorer
Sonar Head, GPS, and Acquisition Computer	Surfzone Explorer in Action
Technical Specifications

SINGLEBEAM TRANSDUCER • Odom HT 100 Ultra-Shallow Water Single Beam Sonar o Tx/Rx Frequency: Frequency Agile in 2 Bands - High: 100kHz – 750kHz (manual tuning in 1kHz steps) Resolution: - 0.01 meter, 0.1 feet o Accuracy (corrected for sound velocity) - 200 kHz - 0.01 meter ± 0.1% depth o Output Power: - Up to 600 Watts in both High and Low Bands (range dependent) - <1 Watt minimum o Ping Rate: - Up to 20 Hz in shallow (10m) range o Depth Range: - From 20cm (0.8ft) to 300m (1,000 ft.)d MOTION SENSOR • VT TSS DMS-10 motion sensor o Dynamic heave accuracy: 5 cm o Dynamic pitch & roll accuracy: 0.07o o Output rate: 200 Hz

POSITIONING INSTRUMENTS • Trimble 5700 dual frequency GPS system & RTK-Basestation o Instrument used for topo/bathy positioning and tidal corrections o High precision L1 and L2 measurements o 24 channels L1 C/A code, L1/L2 full cycle carrier o Extremely low latency (20 milliseconds) o RTK-GPS accuracy depends on conditions such as multipath, obstructions, satellite geometry, atmospheric parameters and basestation control quality. - Published horizontal accuracy: 10 mm + 1ppm RMS - Published vertical accuracy: 20 mm + 1ppm RMS SOUND VELOCITY INSTRUMENTS • Odom Hydrographics Digibar Pro sound velocity probe o Sampling rate: 10 Hz o Depth accuracy: > 31 cm o Velocity accuracy: +/- 0.3 m/sec