Upgrading Antennas to Improve Radio Performance

Application Note: Upgrading Antennas to Improve Radio Performance

Summary

Utilizing high quality antennas is a cost effective way to upgrade the performance of an existing radio systems for better RF link margin and higher data/video throughput across many types of terrain and operating conditions.

While many radios are now outfitted with performance-focused antennas direct from the factory, older radios or products that have seen multiple years of field deployment may no longer be matched with the best performing accessories. Upgrading the antennas used with each radio is an easy way to extend the operating life of existing radio stock and ensures those who are using them can communicate when and where they need without technical difficulties.

Testing and reporting performed by Aliter Technologies:

Product support provided by Obsidian Technologies:

Test Parameters

In the fall of 2016 Aliter Technologies tested the Persistent Systems MPU4 radio with three antennas, including one from Southwest Antennas, in three different environments: open field, forest, and urban.

On one side of the test link was a radio stationed at a fixed position, while the other side of the link was moved at specific distance intervals, where SNR (dB) and uplink / downlink speeds (Mbps) were recorded for each antenna type. Each antenna was tested at the same distance during the same weather conditions.

Antenna Selection

The following three antennas were utilized for all testing:

Antenna 1: Southwest Antennas Part # 1085-117

Electrical Properties

• Frequency: 2.2 - 2.5 GHz
• Impedance: 50 Ohms
• VSWR: <2.0:1
• Gain: 4 dBi
• Polarization: Vertical

Antenna 2:

Electrical Properties

• Frequency: 2.2 – 2.5 GHz
• Impedance: 50 Ohms
• VSWR: <2.0:1
• Gain: 4 dBi
• Polarization: Vertical

Antenna 3:

Electrical Properties

• Frequency: 2.2 – 2.5 GHz
• Impedance: 50 Ohms
• VSWR: <2.0:1
• Gain: 2 dBi
• Polarization: Vertical

Radio Specifications

Radios: Persistent Systems MPU4 (Serial Numbers: 15227, 15228)
Firmware Version: 18.5.8f
Frequency: 2327 MHz
Bandwidth: 5 MHz
Maximum Link Distance: 1.98 miles / 3.2 km
Channel Density: 4 - 8 nodes
Max Transmit Power: 2 Watts

Test Results

Test 1: Open Field / Ground Wave

Area of testing: Lat.  48.846895°, Long. 19.476113°
Date: October 25^th, 2016
Weather conditions: Cloudy

Location for open area / ground wave test

Radio 1 and Radio 2

Test 1 Results

Test 1 Conclusions

The Southwest Antennas Part # 1085-117 was able to significantly extend the effective operating distance of the radio, especially with distances in excess of 984 feet / 300 meters. At 1,968 feet / 600 meters, Part # 1085-117 offers nearly twice the uplink and downlink speed of the other antenna options.

Test 2: Forest

Area of testing: Lat. 48.845520°, Long. 19.468930°
Date: October 25^th, 2016
Weather condition: Sunny

Location for forest test

Radio 1 and Radio 2

Test 2 Results

Test 2 Conclusions

Southwest Antennas Part # 1085-117 continues to improve radio performance at all communication distances, offering a significant uplink and downlink speeds beyond 656 feet / 200 meters.

Test 3: Urban

Area of testing: Lat. 49.085009°, Long. 19.619065°
Date: November 23rd, 2016
Weather condition: Sunny
Radio 1 located inside building, 1st Floor

Urban test area locations along roadway

Base radio located on ground floor of center building
 

Radio 1 and Radio 2

Test 3 Results

Test 3 Conclusion

During the urban testing, Southwest Antennas Part # 1085-117 was able to offer strong uplink and downlink speeds even at the far edge of the test area, located 1,148 feet / 350 meters from the base radio.

Conclusion

As testing demonstrates, upgrading to a high-performance antenna is one way to achieve better radio performance in challenging RF environments, and is an easy way to extend the lifespan of radio equipment. For help selecting the proper antennas for your system, contact Southwest Antennas.