In hydrological survey work, practitioners are often confronted with tough challenges. In shallow water areas, complicated water flow makes it difficult for conventional equipment to capture low-flow velocity data with precision. For medium and deep waters, survey operations become exceptionally cumbersome as both effective coverage and measurement stability need to be guaranteed. Cross-section measurements in deep water demand high penetration capacity from instruments, which frequently requires switching to dedicated equipment to finish tasks. The disparate requirements across varying water depth conditions not only raise costs for equipment transportation and field operation but also risk disjointed data continuity resulting from frequent equipment replacement, undermining the efficiency and accuracy of hydrological surveys. The flagship moving-boat ADCP RS3600D developed by CHC Navigation overcomes equipment limitations for measurements across different water depths via innovative technical design, enabling a single instrument to fulfill diverse demands in hydrological surveys.
The outstanding advantage of the RS3600D lies in its tri-frequency combined design. Through the coordinated operation of the 3600kHz ultra-high frequency band, the 1200kHz frequency band and the 600kHz central vertical depth-measuring beam, full-scenario coverage from shallow to deep water is achieved. The 3600kHz ultra-high frequency delivers exceptional resolution to accurately capture low-flow velocity data in ultra-shallow water with centimeter-level measurement precision. It can clearly record detailed variations in water flow even in slow-current areas such as inshore shoals and small rivers. The 1200kHz frequency band is tailored for medium and deep water areas. Supported by stable signal transmission performance, it fulfills measurement requirements for most conventional water bodies and efficiently collects flow velocity and discharge data for urban inland rivers as well as small and medium-sized lakes. The 600kHz central vertical depth-measuring beam is dedicated to deep-water environments. Thanks to its strong signal penetration capability, it operates reliably in deep-water settings including large rivers and reservoirs and guarantees accurate data acquisition for deep-water cross-section measurements.
Beyond the full-depth adaptability brought by the tri-frequency combination, the RS3600D is further optimized in measurement accuracy and operational flexibility. Equipped with ultra-high frequency broadband technology, its transducer is manufactured with micrometer-level processing craftsmanship and supports a maximum ultra-high carrier frequency of 3600kHz. Leveraging ultra-wideband spread-spectrum modulation technology, it achieves a minimum layering resolution of 2 centimeters, a measurable minimum flow velocity below 1 centimeter per second, and a top dead zone of merely 5 centimeters. This enables the device to precisely detect subtle water flow fluctuations under either high or low flow velocity in shallow water, supplying dependable flow velocity and discharge data for hydrological surveys.
Furthermore, the RS3600D innovatively adopts the DFM dual-frequency cooperative measurement technology and intelligent splicing algorithm, which greatly improves the proportion of actually measured discharge in medium and deep water as well as the accuracy of surface-layer measurements, with an available water depth measurement range spanning from 0.05 meters to 40 meters. From shallow waters with low discharge required for ecological monitoring to deep reaches of major rivers involved in hydraulic engineering construction, field personnel can complete surveys across diverse working scenarios solely with one RS3600D instead of frequently switching instruments. This practice cuts down equipment procurement costs, markedly boosts survey efficiency, and facilitates more convenient and precise hydrological data collection.