Overview

COMPACtenna LMR-I Land Mobile Radio Antenna

The COMPACtenna LMR-I Land Mobile Radio Antenna is a high performance, low-profile mobile antenna designed for government and commercial applications, with coverage of three optimized frequency ranges:
-- High VHF 136-174 MHz
-- Low UHF 378-512 MHz
-- High UHF 750-960 MHz

COMPACtenna LMR-I works for analog and digital operation modes for Police, Fire, Sheriff, Emergency Medical, State Highway Patrol, Homeland Security, U.S. Federal, Military and Business-Commercial applications. The LMR-I is an attractive 9 in. tall, cylindrical radome-style antenna with a reliable leaf spring style NMO mount base for standard center-stud style NMO mobile mounts. It may be used for Vehicular or Base Station – Repeater operations by adding an optional CompacCounterpoise.

COMPACtenna LMR-I provides high performance using a unique Electric-Magnetic Field Diversity design. Superior Omni-directional coverage is achieved far beyond what would be expected for the antenna size. The multi-faceted geometric design of the antenna includes "extended flat monofilar spiral Tesla-like coils" that serve as the LCR matching system, resonating as an integral part of the signal field generation. No external or internal electronic lossy matching components are used. This design establishes diverse electromagnetic fields, resulting in signal stability and performance greater than expected in NLOS (Non-Line-Of-Sight) environments, reducing the effects of ionospheric polarization shifts.

COMPACtenna LMR-I Specifications:

* Frequency Coverage: 136-174 MHz, 378-512 MHz, 750-960 MHz
* Power Rating: 100 W VHF; 75 W UHF
* Duty Cycle, Max. Power: 1-minute transmit limit in a 2-minute period
* Repeater Operation: 30W maximum at the antenna
* Maximum Ambient Temperature: 130 degrees F (hotter conditions, sun exposure, limited air flow reduces duty cycle)
* Gain: 3 dBi, nominal (performance greater than predicted based on gain alone in Non-Line-Of-Sight environments
* SWR, nominal: < 2.1:1 140-162 MHz, 400-500 MHz, 750-960 MHz; <2.5:1 136-140 MHz, 162-174 MHz, 378-400 MHz, 500-512 MHz. Best SWR on VHF frequencies when LMR-I antenna is mounted on an upper corner of a vehicle, NOT center mount. Flat style magnetic mounts provide the best SWR results. SWR varies with size and shape of the vehicle.

Documentation