Imagine a high-speed FPV drone navigating a dense forest at 130 km/h. At this velocity, flight paths are obstructed by complex branches, and any trajectory deviation results in a collision.
In such extreme environments, performance depends not on motor power alone but on the perception system. For drones with LiDAR, perception system performance is expressed as LiDAR frequency, measured in Hertz (Hz).
Without a high sampling rate, the drone lacks sufficient spatial data between detection cycles, effectively operating with blind spots during high-speed transit.
What is Hertz Frequency
1. Definition of Hertz (Hz)
Hertz (Hz), the International System of Units measure of frequency, serves as the universal standard for quantifying the rate of a repeating process within a given time interval.
In sensor engineering, Hertz represents how many times a device completes a full acquisition-and-output cycle every second.
For a single-point LiDAR sensor, this figure is referred to as the sampling rate: the number of discrete distance measurements the sensor completes and transmits each second.
A LiDAR sensor for a drone rated at 1,000 Hz, for instance, executes 1,000 laser pulse emissions and corresponding ToF calculations every second.
On high-speed platforms, a higher LiDAR frequency translates directly into denser positional coverage, ensuring smoother tracking of trajectory shifts.
Conversely, insufficient sampling leads to spatial aliasing or discrete gaps during high-speed transit. This creates gaps in spatial data. As a result, flight algorithms cannot detect sudden environmental changes in time, resulting in navigation failure.
2. Sensor Hertz (Hz) Range
Different industries use different terms for the same underlying concept: camera engineers speak of frames per second (fps), radar designers refer to scan rate or refresh rate, and ultrasonic developers use sampling rate or ping rate. In essence, all of these describe how frequently a sensor updates its output.
The labels differ, but the physics is identical: 30 fps, 30 scans per second, and 30 Hz all represent a system that refreshes its output thirty times per second.
| Sensor Type | Typical Frequency Range | Characteristics |
| Camera (Visual) | 30–60 fps | Rich in detail, but computationally intensive and subject to high processing latency and motion blur. |
| Ultrasonic | 10–50 Hz | Effective for low-speed proximity sensing or docking, but too slow for high-speed motion. |
| Millimeter-Wave Radar | 10–20 Hz | Reliable in adverse weather, but lacks the refresh rate for close-quarters agility. |
| Single-Point LiDAR (e.g., TFA300) | Up to 10000 Hz | Superior temporal resolution and low latency for high-speed obstacle avoidance. |
Impact of LiDAR Frequency on Drone Safety
1. Obstacle Detection
The temporal blind spot of drone LiDAR represents the physical distance a UAV travels between two consecutive samples.
At a high-speed cruise of 30 m/s, a 100 Hz LiDAR sensor leaves a 30 cm gap between measurements, whereas a 10,000 Hz sensor narrows the blind spot to just 3 mm.
By minimizing sampling intervals, high LiDAR frequency achieves a near-continuous data stream, effectively eliminating the safety risks of low-frequency perception.
2. The Reaction Chain in High-Speed Scenarios
Obstacle avoidance for high-speed UAVs is not an instantaneous action but a multi-stage latency pipeline:
Sensing: The UAV LiDAR sensor captures a valid ranging measurement.
- Processing: The flight controller (FC) parses the data and evaluates collision risks.
- Decision: The avoidance algorithm calculates the necessary trajectory adjustments.
- Execution: Electronic Speed Controllers (ESCs) and motors respond to the updated commands.
- Physical Response: The airframe initiates a change in heading or altitude.
If the sensing stage is too slow, the entire chain operates on stale data that lags behind reality. High LiDAR frequency compresses the initial latency of this chain, ensuring the flight controller reacts to the environment’s current state.
3. Altitude Hold and Terrain Following
For agricultural spraying, low-altitude cinematography, and close-range SAR operations, maintaining a stable standoff distance from the ground is critical.
Terrain is rarely flat; it undulates with ridgelines, crop rows, rooftops, and sudden drop-offs. At low update rates, the drone sensor may fail to detect abrupt changes in elevation, potentially leading to ground strikes.
4. EO/IR Gimbal Intelligent Focus Tracking
EO/IR gimbals depend on continuous, precise range data to drive autofocus. Without a reliable distance feed, the lens hunts across its full focal range (focus hunting ). In security surveillance and search-and-rescue operations, this translates directly to missed target identification at critical moments.
High-frequency LiDARs provide thousands of updates per second, enabling the focus controller to track slant-range shifts in real-time. This maintains a constant focus lock on the target, effectively mitigating focus hunting and image degradation caused by ranging latency.
Benewake LiDAR
Benewake TFA300 Series elevates measurement frequency to new heights, establishing a sophisticated benchmark for high-speed UAV perception. Available in two configurations: the TFA300-L (ultra-lightweight uncased module) and the TFA300 (IP67-rated industrial housing).
1. Core Technical Advantages
- High-Frequency Performance
Both models boast a LiDAR frequency of up to 10,000 Hz, with an operational range spanning 0.1 to 290 meters. A narrow FOV of <0.5° enables precise locking onto small or slender targets.
- SWaP-C Optimization
Engineered with a minimal footprint and low power consumption, the TFA300 facilitates direct integration into EO/IR gimbals, adhering to the rigorous size and weight constraints of modern UAVs.
- Seamless System Integration
TFA300 series utilizes industry-standard JST GH connectors and supports CAN interfaces to maintain compatibility with next-generation flight controller architectures.
Furthermore, the SDK natively supports the DroneCAN protocol, enabling plug-and-play functionality with leading open-source platforms like PX4 and ArduPilot, which significantly truncates development cycles.
- Robustness in Exterior Lighting
The optical architecture sustains accuracy under ambient light levels up to 100 kLux, guaranteeing stable data output across diverse lighting conditions, from direct midday sun to the high-contrast shadows of a dense forest canopy.
2. Typical Application Scenarios
- High-Speed FPV Racing: Provides continuous, low-latency distance telemetry along the flight axis, allowing the flight controller to maintain precise situational awareness at extreme velocities.
- SAR Drones: Maximizes search area coverage at the fastest possible speed while maintaining a safe clearance, significantly shortening the critical window for rescue operations.
- Logistics & Last-Mile Delivery: Assists drones in precisely sensing ground altitude and obstacles during vertical descent, ensuring smooth landings and protecting both cargo and nearby pedestrians.
- EO/IR Gimbal Intelligent Tracking: Delivers high-frequency range data to the gimbal for consistently sharp focus on the target.
Conclusion
LiDAR frequency is not merely a technical specification; it is a defining factor in how effectively a drone perceives and responds to its environment.
The Benewake TFA300 Series delivers up to 10,000 Hz LiDAR frequency, enabling high-density, low-latency distance measurement for demanding drone applications.
For detailed specifications, integration support, or evaluation inquiries, contact Benewake right now.
