PLS Overview
The detector part of the sensor is a broadband receiver. This picks up a substantial amount of the lightning energy that allows the system to distinguish between ground lightning and cloud lightning.   With a broadband detector the different characteristics of ground strokes and cloud strokes can be identified.  This allows classification of the detected strokes by the PLS sensors.

In a time-of-arrival based system, timing is an important part of the receiver. The PLS receiver uses commercial GPS timing as a reference. The sensor uses a high frequency timing source that makes the timing more stable, accurate and increases the resolution. The timing is constantly monitored and corrected. This results in more accurate lightning locations.

An onboard processor handles communications and monitors the over-all operation of the sensor. It keeps track of the timing system.
The sensor is designed for remote configuration of the hardware. This is accomplished using Field Programmable Gate Array (FPGA) technology. This allows remote configuration of the hardware using bit patterns. Upgrades can be performed without visiting the site.

The sensor is also designed for remote configuration of the software. Software is downloadable over the communications link. The programs are stored in non-volatile memory on the board. It is not affected by power glitches, losses, or outages. Again, upgrades can be performed without visiting the site.


PLS Functionality

• Flexible Communications
• The sensor supports various communications methods. It has an onboard 10-Base-T network controller that allows TPC/IP communications over a network. There is also a standard serial communication circuit for modem or satellite communications.

• Rugged & Reliable Antenna System
• The PLS has two antennas. The first is an active GPS antenna used for the timing reference. The second is a 3-foot whip antenna for stroke detection. Both antennas are small and light weight, have a small wind resistance, and are easily mounted on existing structures without requirements of extensive civil works. They are designed for easy maintenance, and since there are no sensitive electronics mounted outdoors, site selection is simplified and reliability enhanced.

• Comprehensive Diagnostic Capabilities
• Built-in diagnostics monitor the system and allow remote diagnostics using RSD as long the simple communications software is running. Additionally, a very extensive diagnostic program called RSD can be run, if more in-depth troubleshooting is needed.  Sensitivity and other system settings, are user adjustable with RSD, depending upon the needs of system.

• Cloud Lightning Detection
• Cloud strokes generate much higher energy at higher frequencies than cloud-ground strokes, which again, the sensor will identify.   PLS sensors have no problem detecting cloud stroke signatures and are more than capable of detecting far more than 10% of the cloud strokes.