DRAFT FOR COMMENTS
State of Maryland 700 MHz Interoperability Channel Radio Template
X.01 – Radio Channel Access Requirements
The radio template represents a standardized design in which users identify and/or access specific interoperability radio channels. Channels are typically accessed through the use of a switch that manually changes the radio’s operating frequencies. In modern trunked systems where individual channels are assigned automatically by the radio system, the selector switch provides access to “talkgroups” or specific channels.
Depending upon radio model used, the selector switch may depict up to sixteen (“16”) different channels and/or talkgroups. When access to more than sixteen channels/talkgroups is needed, radios may be differentiated by the use of additional switches on the radio device to expand the number of channels/talkgroups accessible to the user. This kind of expansion may come through the use of an A-B-C switch, which typically expands the number of channels/talkgroups up to forty-eight different resources, or a feature that allows the radio user to scroll through multiple “zones” of channels/talkgroups. The most contemporary state-of-the-art mobile and portable radios may provide access for up to 1,250 channels/talkgroups. In Maryland, the number of channels/talkgroups is typically far less than 1,250 as not all users have access to nor need for devices with such capabilities.
The Statewide 700 MHz Interoperability Plan is predicated upon the use of a modern P25 700/800 MHz mobile or portable radio that has a capacity to operate with multiple zones of channels/talkgroups. In recognition of the need for access to many channels/talkgroups to facilitate public safety communications interoperability in any part of the State, the Plan recommends that all governments within the State using 700/800 MHz radios establish a minimum standard that supports at least one hundred and twenty-eight channels/talkgroups. The basis for this recommendation is that nationally and regionally identified interoperability channels exceed the forty-eight channel/talkgroup capacity found in some mobile and portable radios. Additionally, the Plan recognizes that in disaster situations, first responders from any part of the State may be needed in another part of Maryland or even beyond its borders.
In Maryland, the 700 MHz Interoperability Plan notes that the FCC has designated on up to sixty-four channels for nationwide Interoperability. One of the channels is designated as a calling channel and typically would not be used in the “direct” radio-to-radio mode. This suggests that in 700 MHz, there are thirty-two channels for repeated operations and thirty-two channels that can be identified for direct radio-to-radio operations plus one calling channel.
Continuing with national systems, the 800 MHz National Public Safety Planning and Advisory Committee (“NPSPAC”) channels require ten radio switch positions permitting access to the calling channel and well as use of the four “tactical” channels in the repeated or direct radio-to-radio mode.
On a Region 20 basis, which includes all of Maryland, the Regional Interservice (“RINS”) channels are also often programmed into radios. Although the original number of RINS channels was higher in capacity, there are six frequencies commonly remaining for intra-regional interoperability. By programming these channels to operate in with repeaters or in the direct mode, an additional twelve switch positions are required.
Interoperability System / Switch Positions RequiredNationwide 700 MHz / Sixty-four (“64”)
Nationwide 800 MHz / Ten (“10”)
RINS (Regional) / Twelve (“12”)
Total Required Switch Positions / Eight-six (“86”)
It is important to note that the eighty-four channel positions identified in the preceding paragraphs may not provide support for a complete catalogue of required radio resources. In addition to the national Interoperability and RINS channels, the FCC has designated twelve “low-power” 700 MHz channels that can be used either with on-scene Incident Area Network (“IAN”) repeaters or in the direct mode. These channels were incorporated into the Regional Planning Committee Twenty (“Region 20”) Plan. Further, the State of Maryland obtained a license[1] to operate on the channels on behalf of state government as well as all local governments within the State. The use of these channels in the repeated or direct mode potentially adds a required capability for twenty-four or thirty-six additional positions, depending upon the capability of the user’s radio.
In consideration of the use of all national and regional frequencies as well as the low power 700 MHz channels, at least one hundred and ten (“110”) channel positions would be ultimately required. This results in a recommended guideline for the acquisition of 700/800 MHz radios with a channel/talkgroup capacity of at least one hundred and twenty-eight (“128”) channels to support the interoperability and low-power channels identified above plus a rudimentary capability for channels/talkgroups within the owner’s jurisdiction.
As a practical matter, the Plan anticipates that most users will acquire radios with a greater capability to provide for channels/talkgroups for national, regional and low power operations as well as their day-to-day local operations and interoperability with adjoining jurisdictions.
X.02 – Interim Recommended Channel Configuration
The Plan recognizes that there is likely to be a multi-faceted deployment of 700 MHz Interoperability channels throughout Maryland. As a first step for the utilization of the 700 MHz Interoperability channels, the Plan notes that most users will employ these channels in the “direct” or radio-to-radio mode. Through use of the 700 MHz Interoperability channels in the “direct” radio-to-radio mode, Maryland’s first responders will have many additional radio channels for on-scene operations. When used with thirty-watt mobile transceivers supported by a mobile tower mount antenna, the range of these on-scene systems may be five to ten miles depending upon terrain and other propagation factors. The range of mobile/portable radios directly communicating with other mobile/portable radios will be less and again depend upon terrain and related factors impacting signal propagation for signal coverage.
Eventually, the Plan anticipates that fixed base stations and other infrastructure will be installed within Maryland to support the use of the 700 MHz Interoperability channels in their ultimate configuration. However, in this Interim Phase of deployment, the Plan recommends that a standard Maryland 700/800 MHz template be employed that deploys channel resources in a uniform manner. The Interim Phase of the Plan calls for channels to be configured in the direct radio-to-radio mode with assignments based upon first responder discipline plus tactical channels available for any first responder.
X.03 – 700 MHz Interoperability Law Enforcement/Fire/EMS Templates – Interim Phase
The interim recommended template is predicated upon the use of the four (“4”) nationally designated law enforcement, fire, or EMS 700 MHz Interoperability channels plus twelve “tactical” channels used by all first responders. The four channels identified by user type would be used by the respective disciplines only. For multi-jurisdictional law enforcement, encrypted operations would be permitted on law enforcement Interoperability channels.
In recognition that many jurisdictions within Maryland provide fire and EMS services through one department, the intra-discipline fire and EMS channels should be used based upon the applicable service function of the user. However, the Plan grants broad discretion to local jurisdiction fire chiefs or incident commanders to assign intra-service fire and EMS channels as needed. When cross-discipline Interoperability channels are needed, there are twelve “tactical” channels that may be used by first responders.
The recommended “interim” template for the programming of 700 MHz radios is depicted below.
Radio Zone/Channel / 700 LAW IO / 700 FIRE IO / 700 EMS IO1 / 7LAW61D / 7FIRE63D / 7MED65D
2 / 7LAW62D / 7FIRE64D / 7MED66D
3 / 7LAW81D / 7FIRE83D / 7MED85D
4 / 7LAW82D / 7FIRE84D / 7MED86D
5 / 7TAC51D / 7TAC51D / 7TAC51D
6 / 7TAC52D / 7TAC52D / 7TAC52D
7 / 7TAC53D / 7TAC53D / 7TAC53D
8 / 7TAC54D / 7TAC54D / 7TAC54D
9 / 7TAC55D / 7TAC55D / 7TAC55D
10 / 7TAC56D / 7TAC56D / 7TAC56D
11 / 7TAC71D / 7TAC71D / 7TAC71D
12 / 7TAC72D / 7TAC72D / 7TAC72D
13 / 7TAC73D / 7TAC73D / 7TAC73D
14 / 7TAC74D / 7TAC74D / 7TAC74D
15 / 7TAC75D / 7TAC75D / 7TAC75D
16 / 7TAC76D / 7TAC76D / 7TAC76D
X.04 – 700 MHz Radio Template (Future)
The Plan anticipates that Maryland will have fixed 700 MHz Interoperability base stations in the future providing stand-alone and wide area repeater stations located throughout the State and established Interoperability areas. When this occurs, the radio template must be changed and will be differentiated by fixed stations designed to provide one-site repeater operations as well as “wide-area” stations providing single-channel radio coverage over a wide area; e.g. MESIN, CMARC, NCR, SMIEC, and WAGIN.
The future plan will segregate channels in two ways. In the “7 NAT ____” zone, users will access intra-discipline Interoperability channels as well as the “wide area” Interoperability channels described in the previous paragraph. In another zone, users will have access to the remaining “tactical” channels. Law enforcement radios would program “7 NAT LAW”, fire vehicles should program “7NAT FIRE” etc. Conversely, the “7 NAT IO 1” zone would be programmed uniformly in every first responder radio. For the remaining channels in the additional zone, the zone identifier “7 NAT IO” is recommended (IO stands for Interoperability).
Radio Zone/Channel / 7 NAT LAW / 7 NAT FIRE / 7 NAT EMS1 / 7LAW61 / 7FIRE63 / 7MED65
2 / 7LAW61D / 7FIRE63D / 7MED65D
3 / 7LAW62 / 7FIRE64 / 7MED66
4 / 7LAW62D / 7FIRE64D / 7MED66D
5 / 7LAW81 / 7FIRE83 / 7MED85
6 / 7LAW81D / 7FIRE83D / 7MED85D
7 / 7LAW82 / 7FIRE84 / 7MED86
8 / 7LAW82D / 7FIRE84D / 7MED86D
9 / 7TAC73 / 7TAC73 / 7TAC73
10 / 7TAC73D / 7TAC73D / 7TAC73D
11 / 7TAC74 / 7TAC74 / 7TAC74
12 / 7TAC74D / 7TAC74D / 7TAC74D
13 / 7TAC75 / 7TAC75 / 7TAC75
14 / 7TAC75D / 7TAC75D / 7TAC75D
15 / 7TAC76 / 7TAC76 / 7TAC76
16 / 7TAC76D / 7TAC76D / 7TAC76D
Radio Zone/Channel / 7 NAT IO 1
1 / 7TAC51
2 / 7TAC51D
3 / 7TAC52
4 / 7TAC52D
5 / 7TAC53
6 / 7TAC53D
7 / 7TAC54
8 / 7TAC54D
9 / 7TAC55
10 / 7TAC55D
11 / 7TAC56
12 / 7TAC56D
13 / 7TAC71
14 / 7TAC71D
15 / 7TAC72
16 / 7TAC72D
As noted in other chapters of the Plan, there is no 700 MHz calling channel for Maryland as access to these channels will be made through “8CALL90” and contact with the Maryland Joint Operations Center (“MJOC”). Additionally, there are certain other 700 MHz Interoperability channels that may be employed in a third radio zone. The Maryland Plan provides for 7CALL50 and 7CALL50D to be included in the template; however, the intent is to have the channels incorporated into the template in the event that first responders are called to other states.
Maryland has also worked with the National Public Safety Telecommunications Council (“NPSTC”) to propose a change in 47 CFR §90.531(b)(7) of the FCC rules to permit the current “secondary trunking channels” to be used for air-to-ground radio communications. NPSTC has also proposed to the FCC that 7CALL70 be reallocated to provide for travel coordination when first responders must travel to the scene of an emergency in areas with which they are unfamiliar.
A third 700 MHz Interoperability zone is recommended that provides access to these channels which are unlikely to be used within Maryland on a day-by-day basis. The proposed name for this zone is “7 NAT IO 2”.
Radio Zone/Channel / 7 NAT IO 21 / 7CALL50
2 / 7CALL50D
3 / 7TRVL70*
4 / 7TRVL70D*
5 / 7GTAC57
6 / 7GTAC57D
7 / 7GTAC77
8 / 7GTAC77D
9 / Future Air-to-Ground*
10 / Future Air-to-Ground*
11 / Future Air-to-Ground*
12 / Future Air-to-Ground*
13 / Future Air-to-Ground*
14 / Future Air-to-Ground*
15 / Future Air-to-Ground*
16 / Future Air-to-Ground*
* Proposed change pending approval
X.05 – 700 MHz Low-Power Channels
700 MHz Low-Power channels are not under the control of the states, but the Regional Planning Committees. Technically, these channels, although nationally uniform in designation, are to be used as designated by the Regional Planning Committees. Region 20, which covers all of Maryland, has developed a plan for the use of the 700 MHz low-power channels and readers are directed to that Plan for guidance in the use of these channels.
A copy of the radio license for the State of Maryland government as well as its counties, cities, and towns, is appended to this chapter as a reference.
X.06 – 800 MHz National Public Safety Planning and Advisory Committee (“NPSPAC”) Channels
The FCC has designated a national 800 MHz Interoperability channel for calling as well as four “tactical” channels. As a guideline for Maryland jurisdictions to consider, the 700 MHz Interoperability Channel Plan makes reference to these channels and repeats the nationwide proposed designation established by APCO, NPSTC, and ANSI.
Radio Zone/Channel / 8 NAT IO1 / 8CALL90
2 / 8CALL90D
3 / 8TAC91
4 / 8TAC91D
5 / 8TAC92
6 / 8TAC92D
7 / 8TAC93
8 / 8TAC93D
9 / 8TAC94
10 / 8TAC94D
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[1] See WQJU874