Introduction to MOTOTRBO
MOTOTRBO is the professional-grade digital radio line from Motorola Solutions—not to be confused with Motorola Mobility, the consumer cell phone division sold to Lenovo (a Chinese company) over a decade ago. Motorola Solutions retained the company’s original mission, focusing on critical communications infrastructure such as two-way radio systems for public safety, education, utilities, and enterprise.
Frequency Bands and Industry Trends
While MOTOTRBO supports multiple frequency bands, the primary deployment standard is UHF, especially for new systems. VHF, though still used, is increasingly considered a legacy band—typically retained only when a customer has existing infrastructure.
In urban environments, VHF has become problematic due to frequency congestion and poor FCC coordination, leading to significant interference. In our field experience, even “coordinated” VHF channels are often assigned to adjacent users, creating interference that can reduce effective coverage by over 50%. As a result, we validate frequency performance on-site before committing to any purchase. For most customers, we recommend UHF or, in specific cases, the 700/800 MHz bands. VHF is only advisable for rural deployments where long-distance coverage is paramount.
MOTOTRBO System Types
MOTOTRBO systems come in several configurations:
- Analog Single Repeater
- Digital Conventional
- IP Site Connect
- Capacity Plus
- Linked Capacity Plus (LCP)
- Connect Plus
While the first three are viable for simple needs, Linked Capacity Plus offers the best combination of scalability, spectrum efficiency, and feature set for most enterprise and public-sector clients.
Why Linked Capacity Plus?
Linked Capacity Plus (LCP) is a trunked digital radio system that links multiple sites over IP networks. It works by pooling repeater resources and dynamically assigning them to radios, much like a cloud server cluster. This intelligent resource sharing significantly improves spectral efficiency—often doubling or tripling capacity on the same frequencies.
Given the increasing difficulty of acquiring clean frequencies, maximizing utility from fewer, high-quality channels is a superior approach. However, LCP deployments require a strong understanding of both RF and IP networking—areas where traditional radio technicians sometimes struggle. We’ve encountered multiple customer sites where poor LCP deployments stemmed from a lack of IT and system design expertise.
Keys to a Successful LCP Deployment
1. Site Selection and Frequency Validation
Start with thorough site selection. While RF modeling tools are helpful, they rely heavily on accurate FCC coordination, which is unreliable in congested areas. We recommend validating candidate sites using temporary repeater deployments and tools like RDAC to measure noise floors and assess digital interference.
In one urban VHF test, for instance, a single poorly coordinated frequency delivered less than 1 mile of coverage with severe key-up failures—whereas a clean frequency from the same site yielded 7 miles of range.
2. Engaging IT Early
Never delay IT engagement. LCP requires detailed network configurations—IP routing, VLANs, port forwarding, etc.—and surprise requirements can derail deployments. We use a standardized, field-tested spreadsheet to capture all IT needs up front and ensure alignment with customer IT teams.
3. Benching Before Deployment
Programming must be finalized and tested before field deployment. We bench-test LCP systems in-house, using switch gear that emulates the customer’s environment, including static IP addresses and network segmentation. Field programming or last-minute design decisions are a leading cause of failure in LCP systems.
Building Subscriber Code Plugs
Creating subscriber code plugs is often the most complex and time-consuming part of an LCP deployment. You must consider:
- Channel pool architecture
- Roaming behavior and RSSI thresholds
- Site-specific talkgroup designations
- Feature compatibility across mixed radio fleets
Using default templates is a recipe for failure. We’ve developed proprietary strategies over years of experience that account for real-world performance, user behavior, and future scalability.
We strongly recommend using Motorola’s Radio Management (RM) platform. Once mastered, RM offers:
- Centralized code plug management
- Over-the-Air Programming (OTAP) for live updates
- Error mitigation by allowing remote reprogramming without USB tethering
However, RM has notable limitations: it doesn’t support multi-tenant environments, and databases cannot be merged. Consequently, we maintain separate RM instances per customer, a workaround that Motorola has yet to address—likely because most technicians still avoid RM entirely.
Final Thoughts
Deploying MOTOTRBO Linked Capacity Plus systems is both an art and a science. When executed correctly, they provide unmatched coverage, scalability, and reliability. But doing it right requires deep expertise in both RF engineering and modern IP networking, rigorous planning, and a disciplined, test-driven approach.
At PSI, we’ve designed and deployed dozens of MOTOTRBO systems, and we’ve seen what works—and what doesn’t. If you’re considering a deployment or expansion, our team is ready to bring clarity, precision, and reliability to your radio communications.