Ubiquiti Lite AP GPS (LAP-GPS): The Complete Synchronization Guide

Overview and Introduction

The Ubiquiti Lite AP GPS (LAP-GPS) is a specialized, high-performance GPS antenna designed for one primary purpose: to provide precise timing synchronization for Ubiquiti airMAX networks. It is not a wireless access point but a critical infrastructure component that enables airSync technology, allowing multiple access points to coordinate their transmissions and eliminate self-interference.

Its key feature is the ability to provide a Stratum 1 time source to compatible devices, ensuring all access points in a network broadcast and receive in perfect, alternating time slots. This dramatically increases the capacity and performance of dense wireless deployments.

Key Features at a Glance

• airSync Technology Enabler: Provides GPS timing to synchronize multiple Access Points, eliminating self-interference.

• High-Gain GPS Antenna: Integrated 28 dB low-noise amplifier (LNA) for superior satellite acquisition.

• Dedicated Design: Specifically engineered for Ubiquiti’s airMAX AC platform (Rocket Prism models).

• Simple Integration: Connects directly to compatible devices via a single coaxial cable carrying power and signal.

• Rugged, Weatherproof Housing: IP67-rated radome for reliable outdoor operation in all conditions.

• Increased Network Capacity: The ultimate solution for maximizing performance in multi-AP, high-density deployments.

Full Technical Specifications

Performance and Real-World Use

What is the Lite AP GPS (LAP-GPS) Used For?

1. Eliminating Co-Channel Interference: The primary use. When multiple APs on the same channel are close together, they interfere. airSync uses GPS timing to make them “take turns,” solving this problem.

2. Maximizing Sector Density: Allows a WISP to deploy more access points on a single tower, significantly increasing total subscriber capacity and revenue potential.

3. Precision Timing: Provides a highly accurate time source for network logging and monitoring.

4. Mandatory for Dense Deployments: Essential for urban WISP deployments or any scenario where APs are within range of each other and must use the same limited set of channels.

How airSync Technology Works

• Without airSync: Access Points transmit independently, causing packet collisions and reduced efficiency (like people talking over each other in a room).

• With airSync: Each AP connected to a LAP-GPS gets a microsecond-accurate clock signal. This allows the airMAX AC protocol to create a coordinated TDMA schedule across all synchronized APs, making them transmit and receive in alternating, non-overlapping timeslots (like people speaking in an organized turn-based discussion).

Result: Drastic reduction in noise floor, increased throughput per client, and the ability to reuse channels more aggressively.

Setup and Compatibility Guide

What’s in the Box?

• Lite AP GPS (LAP-GPS) Antenna

• Magnetic Base with 1/4″-20 Thread

• (Note: MMCX to CRC9 cable is NOT included and is often required)

The Critical Requirement: A Compatible Radio

The LAP-GPS is an accessory. It must be connected to a Ubiquiti device that supports airSync and has a GPS input port.

Compatible Devices:

• Rocket 5AC Prism (R5AC-PTMP-GPS) – This is the primary device it’s designed for. It has a dedicated CRC9 GPS port.

• Rocket 5AC Lite (R5AC-LITE-GPS) – The cost-effective version with GPS support.

• Rocket M5 GPS (RM5-TiGPS) – Older MIMO model with GPS support.

Crucial Note on Cables:

The LAP-GPS has an MMCX connector. Most compatible Rockets have a CRC9 port. You must purchase the separate ACC-GPS-ADPT cable adapter to connect the two.

Step-by-Step Installation Process:

1. Place the Antenna: Position the LAP-GPS with a clear, unobstructed view of the sky. This is non-negotiable for GPS lock. Mount it on a metal surface using the strong magnetic base or the threaded hole.

2. Route the Cable: Run the integrated 3-meter cable from the antenna to your Rocket radio. Avoid sharp bends and keep it away from power cables.

3. Connect the Cable: Use the ACC-GPS-ADPT adapter cable to connect the LAP-GPS’s MMCX end to the Rocket’s CRC9 GPS port.

4. Configure the Radio:

   • Access the Rocket’s airOS interface.

   • Navigate to the Settings > airSync tab.

   • Ensure airSync is enabled.

   • The interface will show the GPS status. Wait for it to acquire a “Lock.” This requires a clear sky view and can take several minutes.

5. Verify Synchronization: Once multiple APs have GPS lock, their airSync status will show they are synchronized.

Conclusion:

The Ubiquiti Lite AP GPS (LAP-GPS) is a deceptively simple device that unlocks the full potential of the airMAX AC platform. For any WISP facing the challenges of network growth and co-channel interference, it is not just an accessory but a necessity. By enabling precise airSync time synchronization, this dedicated GPS antenna transforms a crowded, noisy radio environment into a efficient, high-capacity network, proving that perfect timing is everything in wireless communication.