Texas Radio
Communications
Interoperability Plan
One of Governor Perry’s top 2005 Homeland Security objectives is to achieve
Level-41 radio interoperability within the first responder community throughout Texas.
The Texas Radio Communications Interoperability Plan serves as a roadmap to achieve
this objective. State wide Level-4 attainment, simply put, is when fire fighters,
emergency medical responders, police officers, deputy sheriffs and state troopers can
go anywhere in the state and have immediate radio communications with each other
using their own equipment.
Obstacles to radio communications interoperability have vexed the first
responder community for several decades. As the terrorist attacks of 09/11/01 clearly
demonstrated, first responders must have real-time radio communications across
disciplines and jurisdictions. Radio interoperability in Texas is particularly challenging
because of its size (261,797 square miles) and its geographic and demographic
diversity. Certainly, radio communications interoperability could be achieved through
the costly acquisition of entire new radio systems. However, this is neither cost
effective nor necessary with today’s integration technology.
The Texas plan employs a network approach using the demonstrated leadership
at the regional level through Texas Councils of Governments (COGs) and strict
adherence to the Department of Homeland Security’s national technical requirements
for wireless public safety communications and interoperability. This plan leverages
existing radio systems rather than replacing the existing public safety radio
infrastructure in Texas. It was developed with substantial assistance from two industry
leaders that possess the technical expertise necessary to validate the efficacy of this
plan.
The 24 COGs in Texas have the responsibility of developing and implementing
regional strategies to provide Level-4 radio communications interoperability within their
regions. This will result in first responder interoperability within a COG and among other
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Texas has adopted the Department of Homeland Security definitions for the six levels of interoperability.
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COGs that have achieved Level-4 interoperability. State-wide interoperability will be
achieved once all of the COGs achieve Level-4 status.
Several regions have already made substantial progress toward interoperability.
For example, the Houston-Galveston Area Council of Government has substantial
interoperability in the urban areas and is in the process of upgrading radio system
capabilities in the outlying counties to provide region-wide Level-4 interoperability or
higher. In addition, the regional leadership in South Texas has developed an
implementation plan that will provide Level-4 interoperability from Brownsville to El Paso
providing coverage along the entire Texas/Mexico border. This project already has
been fully funded with Fiscal Year 2004 grants.
The Office of the Governor recognizes that there are several important Homeland
Security initiatives throughout the state that require funding. However, to achieve this
vital objective, COGs should prioritize the expenditure of Office of Domestic
Preparedness (ODP) grant funds on radio interoperability projects within their respective
regions.
Interoperability is essential to effective emergency management both during a
crisis and on a daily basis. At the most basic level, interoperability allows two or more
parties to exchange information directly. First responder personnel at the scene can
instantly connect and communicate with each other, make the contacts needed to bring
in additional resources, coordinate rescue missions and provide other forms of
response to threats and emergencies. For purposes of this plan, first responder
agencies include local and tribal fire departments, emergency medical services, police
and sheriffs departments and the Texas Department of Public Safety.
The frequencies most in use within Texas for public safety are VHF (Very High
Frequency) and 800 MHz. In some areas UHF (Ultra High Frequency) is still in use. In
the future, the emerging 700 MHz band will have dedicated interoperability channels.
However, the migration to 700 MHz may not happen for years. VHF frequencies have
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been in use for over 30 years and provide coverage to approximately 80 percent of the
geography in the state of Texas. However, because of the lack of available spectrum
and other technical limitations associated with the VHF band, several of the
metropolitan areas in Texas have moved to the newer 800 MHz band. Approximately
80 percent of the population in Texas is covered by 800 MHz systems. UHF
frequencies are still in use by some police departments, volunteer fire departments, and
emergency medical services.
Texas has adopted the Department of Homeland Security definitions for the six
levels of interoperability to assess different levels of interoperability throughout Texas.
The COGs and the Governor’s Office of Homeland Security will use the definitions
below as a way to assess regional status and progress.
Level-1 Swap Radios:
The simplest and most basic level of interoperability is the physical exchange of radios
with other agencies involved in an event. However, it is impractical for every agency to
have extra radios on hand for each member of every other possible agency that could
appear on-scene, especially for larger scale events.
Level-2 Talkaround or “Directed Net”:
Talkaround provides interoperability where multiple radio users talk radio-to-radio on the
same transmit and receive frequency in the conventional mode. In this situation,
communications are tightly bound by the air interface: the same frequency is required
and transmissions are digital-to-digital or analog-to-analog, not analog-to-digital.
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Level-3 Mutual Aid:
Level 3: Mutual Aid
VHF
Interop
Repeater
VHF
Interop
Repeater
VHF
Interop
Channel
VHF
Interop
Channel
Mutual aid channels provide operability for first responder radios and interoperability
between radios within the same frequency band…i.e. VHF users can only talk to (or on)
other VHF systems. The effectiveness of Mutual Aid Level-3 can only be achieved
through adherence to predetermined protocols and procedures as part of the National
Incident Command System (NIMS) which is used in the event of an emergency.
Level-4 Gateway (Console Patch):
Level 4: Cross band Repeaters
Level 4: Deployable RF Gateways
VHF
VHF
Interop
Repeater
VHF
Interop
Channel
System
800Mhz
NPSPAC
Repeater
Field
Deployed
Gateway
….
….
OR
….
800Mhz
NPSPAC
Channel
Gateway in Vehicle
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800 MHz
System
Level 4: Fixed Gateway -- Interface Box
Level 4: Gateway -- Console Patch
800 MHz
System
VHF
VHF System
800 MHz
System
System
Gateway
Audio, System data,
control info
Audio Only
Audio Only
Audio Only
A gateway is a generic term for devices that connect multiple frequency bands and/or
coverage areas and thereby provide interoperability between them. Overlapping
coverage areas may use wired or wireless gateway devices. For overlapping coverage
areas operating in different frequency bands, wireless gateway devices provide crossband interoperability for the radios (require separate Transmit Receivers (T/R)
frequencies). For overlapping or non overlapping coverage areas, wireline
interconnectivity also can be used to provide cross-band operation for the radio users
while also providing connectivity to and/or between dispatchers and systems. Gateway
devices may be used to provide wireline or wireless interoperability between the
coverage areas of Mutual Aid channels or existing systems or a combination of both.
These systems and coverage areas may be single-site or multi-site, analog or digital,
conventional or trunked, proprietary or standards based. Interoperability will be limited
to the lowest common capability that these systems provide.
Level-5 System-Specific-Roaming (Trunked and Conventional):
Level 5: System Specific Roaming
County A
County B
County B
County A
System
Controller
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System
Controller
Additional interoperable capabilities for first responder incident management can be
provided by leveraging existing systems using mutual aid talk groups. These systems
typically have more capabilities and greater capacity than Mutual Aid channels. A
greater level of interoperability for first responders can be achieved by leveraging the
existing systems. These systems may be in a variety of frequency bands, may be
analog or digital and conventional or trunked. Existing systems are owned by specific
agencies and may come from a variety of vendors.
Level-6 Standards Based Shared Systems (Trunked and Conventional):
Level 6: Standards-Based Shared Systems
Vendor B
800 MHz
Vendor A
800MHz
Vendor B
VHF
P25-ISSI
Vendor A
VHF
Standard based systems ensure that the radios and/or the infrastructures use
technology and messages that are interoperable regardless of the equipment vendor.
By sharing standards based systems with first responders, a greater level of
interoperable features with greater capacity can be achieved. Level-6 systems may be
conventional or trunked, single or multi-site. They must be based on the P25 CAI
standards (ANSI/TIA/EIA-102) and conform to SAFECOM interoperability standards.
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Techniques
Level Interoperability
Method
Fit
Standards-Based
Shared Systems
Most Complete Long-Term
Solution
System-Specific
Roaming
Full-featured, Wide Area
Gateway
(Console Patch)
Short-Term
System Modification
Well Known With Public
Safety Agencies
Mutual Aid
Channels
Talkaround
Swap Radios
Easily deployed
Simple Short-Term
Solutions
Time-consuming
Whenever possible, the COGs will bypass lower levels of interoperability to
achieve statewide, standards-based interoperability. Level-4 will provide a solid
foundation for future technology upgrades. All new radio infrastructure and subscriber
equipment acquisitions must be Project 25 Common Air Interface (CAI) compliant. To
the greatest extent possible, existing radio systems and infrastructure should be used to
achieve interoperability rather than replacement. State-owned radio towers will be used
to facilitate this integration wherever necessary. There may be instances in which a
COG will be unable to quickly achieve Level-4 interoperability. In those instances, the
short-term objective will be to bypass Level-1 & 2 to achieve Level-3 interoperability.
All state agencies that have the responsibility to either approve or administer
federal and state grants will ensure that all grants for radio communication projects
adhere to the standards set forth in this plan. Moreover, state agencies will ensure that
future upgrades to their radio communication systems are in compliance with this plan.
As previously noted, the Texas Department of Public Safety is considered a part of the
first responder community and will develop an agency specific plan to achieve Level-4
radio interoperability throughout the state working with the COGs. Although other state
law enforcement agencies are not considered as a part of the first responder
community, these agencies often play a vital support role. Moreover, interoperability will
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enable them to be more effective in carrying out their responsibilities. Therefore, these
agencies will develop agency specific plans to achieve interoperability with the first
responder community within each COG.
The COGs will submit project proposals to Texas Engineering Extension
Services, with the state administering office for Fiscal Year 2005 ODP funding. The
proposals should identify the first responder community within their region by agency
name and provide an update of their interoperability status as defined by the DHS’s six
levels of interoperability detailed in this plan. The project proposal should include
sufficient details as to how all first responders within the COG will achieve Level-4
interoperability along with milestones and projected time lines.
The Governor’s Office of Homeland Security will be responsible for tracking the
progress of each COG and state agency and will provide the Governor periodic
updates.
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