PODCAST: comprehensive overview of the Houston Radar SpeedLane Pro, a non-intrusive, dual-beam traffic sensor. They detail its technical specifications, including its K-band FMCW radar operation for simultaneously detecting and tracking up to 16 vehicles, measuring their speed, length, direction, and calculating traffic flow parameters like volume, occupancy, and gap. The sources also cover installation guidelines, emphasizing side-fire mounting, optimal height and setback, and the use of the integrated HD camera and StatsAnalyzer software for setup and alignment. Furthermore, they outline communication options such as Bluetooth, Ethernet, and serial connections, data protocols for real-time and historical data retrieval, power requirements, and the functionality of optional components like the built-in battery, solar charger, and cellular modem, along with information on quality control and available technical support.
The SpeedLane Pro addresses varied installation environments and operational requirements through a combination of its flexible physical design and mounting options, robust environmental capabilities, diverse communication and powering solutions, comprehensive software for precise configuration, and demonstrated accurate performance across different traffic conditions.
Here’s a breakdown of how it achieves this adaptability:
- Flexible Physical Installation and Mounting:
- The SpeedLane Pro is a side-firing radar solution, designed to be mounted across traffic at a 90° angle to the roadway, capable of covering one or more lanes.
- It comes standard with a universal pole mounting bracket that allows for sufficient adjustment of the radar’s pointing angle across various mounting heights and setback lengths. Optional Quick Adjust Clamps are also available for easier alignment, especially for portable or frequently moved installations.
- The radar allows for setback lengths as short as 2 feet (0.6m) from the closest lane, provided it is mounted at least 17 feet (5.2m) from the ground. For optimal performance, the mounting height should typically be between 1.2 and 1.4 times the setback distance. Detailed installation tables are provided with recommended, minimum, and maximum mounting heights for various setback distances.
- It can be mounted behind a pole to maximize setback in locations with limited space.
- The design emphasizes rigid mounting to prevent swaying, which could otherwise affect performance.
- Robust Environmental Capabilities:
- Housed in a tubular NEMA 4X Lexan polycarbonate weatherproof enclosure, the device is UV-stabilized and built to withstand harsh conditions, meeting NEMA 4X standards for wind, moisture, dust, and airborne particles, and IEC standards for shock and vibration resistance. It also boasts an IP66 rating and an IP67 M12 data/power connector for protection against dust and water ingress.
- It operates over a wide temperature range, from -40°F (-40°C) to +167°F (+75°C) without an internal UPS, and -4°F (-20°C) to +131°F (+55°C) with the optional internal UPS.
- To adapt to varying environmental conditions and weak signals, it features Automatic Gain Control (AGC) per lane.
- The SpeedLane Pro actively manages its detection zone by creating and continuously adjusting a Clutter Map to filter out stationary targets like fences, signs, and structures. The Clutter Time Constant (CTC) can be adjusted by the user from 1 second to 300 minutes, allowing the radar to adapt to different traffic flow conditions, such as stopped or highly congested traffic.
- Diverse Communication and Powering Options:
- Power: It supports a wide DC input voltage range of 9VDC to 28VDC.
- An optional Power over Ethernet (PoE) module allows powering via Ethernet using the 802.3af. Mode A/Type 1 standard.
- For temporary or permanent solar installations, an optional built-in 96 WHr LiFePO4 rechargeable battery with a Maximum Power Point Technology (MPPT) solar charger is available. The battery can also be charged by an external 24V AC to DC adapter or a 12VDC external battery.
- Its ultra-low power consumption (1.0 Watts in standard configuration) prolongs battery life and allows for smaller, more efficient power setups.
- Communication:
- It offers a software-configurable serial interface (RS-232, RS-422, or RS-485) supporting multiple baud rates.
- A standard built-in Class 1 long-range Bluetooth radio provides wireless connectivity up to 800 feet (243 meters) outdoors, with an Android app also available for setup and viewing.
- An optional 100 Mbps Ethernet port facilitates easy connection using “Zeroconf” networking, eliminating the need for manual IP address configuration.
- For remote access, an optional built-in 4G LTE cellular modem (or 3G) with GPS allows the device to operate as a self-contained “monitoring node” that can push data to a central server. The modem’s power usage can be minimized by regulating its duty cycle.
- Data Management: The SpeedLane Pro stores up to 1 million individual vehicle records and 3 months of interval data in onboard non-volatile memory, managed by a battery-backed Real-Time Clock. Data can be retrieved via SQL queries or a REST API, supporting both polling and event-driven models. Houston Radar’s Tetryon Cloud Server can aggregate data from multiple devices, provide browser-based reporting, and backfill missing data after communication outages.
- Power: It supports a wide DC input voltage range of 9VDC to 28VDC.
- Software-Driven Configuration and Optimization:
- The Houston Radar StatsAnalyzer Windows application provides an intuitive graphical user interface (GUI) for setup and configuration.
- Its Installation Wizard guides users through alignment steps using a live video feed from the built-in HD camera with an on-screen crosshair and electronic level readings, ensuring precise vertical and horizontal alignment.
- Users can define up to 16 configurable lanes in 1-foot (0.3m) increments, drawing boundaries around real-time histogram peaks of detected vehicles, which simplifies lane setup without complex calculations.
- The SpeedLane Pro features advanced “application filters” to optimize performance for various scenarios, including options to improve performance in installations with multi-path reflections.
- It allows for user-configurable speed and length bins for detailed vehicle classification and data analysis.
- Accurate Performance Across Diverse Traffic Conditions:
- The patented true dual-beam FMCW radar technology enables “virtual speed traps” for highly accurate measurements of speed, direction, and length without the need for in-situ calibration. It uses an advanced tracking algorithm to simultaneously detect, measure, and track multiple targets.
- While optimized for “nominal traffic conditions”, an independent evaluation by TxDOT demonstrated the SpeedLane Pro’s strong performance even under highly congested conditions with slow speeds (below 20 mph) and in lanes furthest from the sensor.
- In this evaluation, the SpeedLane Pro’s total volume counts were consistently within 2-3% of ground truth, outperforming another radar that showed larger discrepancies in similar conditions.
- Its vehicle classification accuracy was also notably higher, with small deviations from ground truth for all vehicle classes (small, medium, large), even in distant lanes.
- It has a broad range detection capability from 5 to 100 MPH (8-160 km/h).
The SpeedLane Pro detects vehicles primarily through its true dual-beam Frequency Modulated Continuous Wave (FMCW) radar technology. This advanced radar system is designed for non-intrusive traffic data measurement and collection.
Here’s a detailed breakdown of its detection mechanism:
- FMCW Principle and Virtual Speed Traps
- The SpeedLane Pro utilizes dual FMCW radars that modulate the frequency of the transmitted signal in a linear fashion.
- By analyzing the difference between the frequencies of the local oscillator and the signal returned from a target, the radar can determine the distance to the target.
- For moving targets, it also takes into account the Doppler shift of the return signal.
- The radar uses a double linear ramp modulation, first increasing and then decreasing the frequency, which allows it to measure both the range and velocity of the target.
- The patented dual radars set up “virtual speed traps” in 0.375-inch increments in front of the device. This enables the SpeedLane Pro to accurately measure the speed, direction of travel, and length of each vehicle.
- It employs an advanced target tracking technique based on a proprietary algorithm that allows it to simultaneously detect, measure, and track multiple targets.
- Radar Detection Zone and Target Characteristics
- The radar detection zone is oval-shaped, defined by its 7°x74° beam and incident angle to the road surface. The wide vertical angle (74 degrees) allows for simultaneous detection from lanes at minimum offset to maximum range, while a narrow horizontal beam width helps resolve closely following vehicles in congested traffic at far ranges.
- The strength of a detected target is determined by its radar cross-section (RCS), which depends on the target’s material, exposed area, shape, and the incident angle of the radar beam.
- Large, flat metallic surfaces positioned at exactly 90° to the incident radar beam (like vehicle sides, front, and rear ends) make the best targets. Surfaces joined at a 90° angle, such as a corner of a pickup truck bed, create a perfect reflector, resulting in a very strong return signal.
- In a side-firing configuration, as a vehicle passes in front of the radar, the incident angle momentarily becomes 90°, leading to a strong return signal.
- Adaptation to Varied Environments and Traffic Conditions
- Clutter Map: The SpeedLane Pro actively manages its detection zone by automatically creating and continuously adjusting a Clutter Map. This map is used to filter out stationary targets, such as traffic signs, structures, and fences, from the signal, ensuring only true moving targets are reported. Users can define a Clutter Time Constant (CTC), ranging from 1 second to 300 minutes, to control how quickly stationary targets fade into the background. This is crucial for adapting to different traffic flow conditions, including stopped or highly congested traffic.
- Automatic Gain Control (AGC): It features Automatic Gain Control per lane to automatically adjust for weak signals, installation effects, and environmental conditions, enhancing performance and maintenance.
- Multi-Path Reflections: The device includes advanced “application filters” and configuration options to improve performance in installations prone to multi-path reflections (where radar signals bounce off walls or other structures, creating “ghost” targets). Adjustments to radar location can sometimes make these ghost targets fall outside user-defined lanes, thus being discarded.
- Performance in Congested Conditions: An independent evaluation by TxDOT showed that the SpeedLane Pro maintained strong performance even under highly congested conditions with slow speeds (below 20 mph) and in lanes furthest from the sensor. Its total volume counts were consistently within 2-3% of ground truth, and its vehicle classification accuracy was notably high across various vehicle classes.
- Installation and Sighting Assistance
- The SpeedLane Pro is a side-firing radar solution, meaning its beam points across traffic at a 90° angle to the roadway.
- A built-in HD video camera and electronic level sensor aid in precise vertical and horizontal alignment during installation, providing a live video feed or snapshots with an on-screen crosshair and level readings. This visual confirmation helps ensure the radar beam is correctly pointed and covers all desired traffic lanes.
^ Some Pricing Information