Types of Motorola Trunking Systems
Types of Systems:
| Type I Systems | Motorola Type I Systems refer to the original Motorola systems that were based on Fleets and Subfleets. Each system had a certain number of Fleets assigned, and then each Fleet had a certain number of Subfleets and radio ids. The distribution of Fleets and Subfleets on a Type I system is determined by the system Fleetmap. Motorola Type I systems are not scalable because they limit the amount of IDs any fleet or subfleet can support. |
| Type II Systems | Motorola Type II systems refer to the the second generation Motorola Trunking systems that replaced Fleets and Subfleets with the concept of talkgroups and individual radio IDs. There are no dependencies on Fleetmaps, therefore there are no limitations to how many radio ids that can participate on a talkgroup. This allows for greater flexibility for the agency. |
| Hybrid Systems | A Motorola Hybrid system has "blocks" of the system that are Type I Fleets/Subfleets and Type II talkgroups. All radios may be Type II, or the Type I radios might be used exclusively in subfleets while the Type IIs are used exclusively in talkgroups. |
| Type IIi Systems | Motorola Type IIi Hybrid is a system that has Type I fleets and subfleets, and has Type II radios that are able to use those Type I fleet/subfleets. The common reason that an agency sets up a Type IIi Hybrid system is because they have newer Type II radios that they want to interoperate with older Type I radios, without having to create new Type II talkgroups |
| Type IIi Hybrid Systems | A mixture of Hybrid and IIi |
Flavors of Motorola Trunking Systems:
| Type I (Privacy Plus) | The term Privacy Plus refers to a Type I system. Privacy Plus systems are normally older Public Safety systems and SMRs (Specialized Mobile Radio - Businesses who rent out space on trunking systems) |
| Type II (Smartnet ) | The term Smartnet refers to
a set of features made available for Public Safety users. This includes better
security, emergency signaling, dynamic regrouping, remote radio monitoring, and other
features. The following is true of a Type II Smartnet system.
|
| Smartzone | Smartzone
systems are Smartnet Type II systems
that are networked together via Microwave or Land-line to provide multi-site wide area
communications. Radios affiliate with a particular site, and affiliate with a
talkgroup which allows the radio to talk on that talkgroup to other radios on other sites.
Many large public safety and state agencies use SmartZone system for wide area
communications. The following are the characteristics of a Motorola Smartzone
system:
Monitoring a Smartzone system with a Trunktracker is the same process as monitoring any other Smartnet Type II system, except that you can only monitor one site at a time. For you to monitor a specific talkgroup on a Smartzone site, someone's radio must be affiliated to that specific talkgroup. Therefore, if you are monitoring talkgroup "POLICE-NORTH" on a site where no radios have that talkgroup affiliated, then you will not hear any communications on that talkgroup until a radio affiliates to that talkgroup |
| Smartzone OmniLink | Smartzone
OmniLink provides a broad range of robust system features and utilizes a
distributed call processing architecture which links up to four multi-site
Smartzone™ systems together into one seamless network, supporting up to
192 sites.
Typical users of Smartzone OmniLink systems include organizations who have vast geographic requirements -- such as Electric and Gas Companies, and extremely Large Public Safety agencies. |
| Simulcast | The term simulcast refers to the process of setting up multiple repeaters to transmit exactly the same communications on the same frequency. Many agencies setup Simulcast systems to increase coverage of their single site Motorola system. 1 Site Controller....multiple transmitters. |
Converting Talkgroups, Subfleets, Fleets, and Size Codes.
The easiest way to convert talkgroups between their various formats is by using the Windows scientific calculator. It provides a Decimal to Hex function that works very well.
Type II talkgroup IDs come in three flavors: Uniden Trunktracker format such as 41072. ID Range: (0 - 65504) Motorola 3 digit Hex variety such as A07. ID Range: (000 - FFE) Motorola 6 digit decimal variety such as 802567. ID Range: (800000 - 804094) In the following formulas, M3 represents a Motorola 3 digit Hex format value, M6 represents a Motorola 6 digit decimal format value, and U represents a Uniden format value. The notation Dec_to_Hex(X) means convert X to its Hex equivalent. The notation Hex_to_Dec(X) means convert X to its Decimal equivalent. To convert Use this Formula ---------- ----------------- M6 to U (M6 - 800000)*16 = U M6 to M3 Dec_to_Hex(M6 - 800000) = M3 M3 to U Hex_to_Dec(M3)*16 = U M3 to M6 Hex_to_Dec(M3) + 800000 = M6 U to M3 Dec_to_Hex(U/16) = M3 U to M6 U/16 + 800000 = M6 Examples: Convert the M6 format ID, 802617 to U format: (802617 - 800000)*16 = 41872 Convert the M6 format ID, 802617 to M3 format: Dec_to_Hex(802617 - 800000) => Dec_to_Hex(2617) = A39 Convert the M3 format ID, A39 to U format: Hex_to_Dec(A39)*16 => 2617*16 = 41872 Convert the M3 format ID, A39 to M6 format: Hex_to_Dec(A39) + 800000 => 2617 + 800000 = 802617 Convert the U format ID, 41872 to M3 format: Dec_to_Hex(41872/16) => Dec_to_Hex(2617) = A39 Convert the U format ID, 41872 to M6 format: 41872/16 + 800000 = 802617 |
Type II Special Status Bits
Type II Smartnet systems use these status bits for special transmissions such as Emergency, Patches, DES/DVP scrambled transmissions, and Multiselects on Motorola Trunking systems. Motorola Trunking radios directly interpret them for their special functions, thus no difference is noticed by the person with the radio. The Trunktracker scanners however interpret these special talkgroup status bits as different talkgroups entirely. Below is the conversion chart for these special status bits.
| TTID + # | Usage |
| ID+0 | Normal Talkgroup |
| ID+1 | All Talkgroup |
| ID+2 | Emergency |
| ID+3 | talkgroup patch to another |
| ID+4 | Emergency Patch |
| ID+5 | Emergency multi-group |
| ID+6 | Not assigned |
| ID+7 | Multi-select (initiated by dispatcher) |
| ID+8 | DES Encryption talkgroup |
| ID+9 | DES All Talkgroup |
| ID+10 | DES Emergency |
| ID+11 | DES Talkgroup patch |
| ID+12 | DES Emergency Patch |
| ID+13 | DES Emergency multi-group |
| ID+14 | Not assigned |
| ID+15 | Multi-select DES TG |
Therefore, if a user was transmitting a multi-select call on talkgroup 1808, the trunktracker would actually receive those transmissions on 1815. Some common uses of these status bits are as follows:
- When a user hits their emergency button, all conversations on the talkgroup revert to the Emergency status talkgroup (ID+2) until the dispatch clears the emergency status. Therefore, if someone hit their emergency button and their radio was on talkgroup 16, all communications would switch to talkgroup 18.
- A lot of Fire and EMS departments dispatch tone-outs and alarms as Multi-select communications (ID+7). Therefore, if your fire department dispatch talkgroup is 1616, and they do dispatch tone-outs and alarms as Multi-selects, then those communications will be on talkgroup 1623.
This can be a problem, because you will miss communications if you don't have those talkgroups programmed. By setting the Type II block you are monitoring with a fleetmap of S-1 (Mot Size A), you'll essentially get Type I subfleets for each Type II talkgroup - encompassing all of the status bits into one subfleet.
Type I Size Codes
| Motorola | A | B | C | D | E | F | G | H | I | J | K | M | O | Q |
| Trunktracker | S1 | S2 | S3 | S4 | S5 | S6 | S7 | S8 | S9 | S10 | S11 | S12 | S13 | S14 |
| Trunker.exe | A | B | C | D | E | F | G | H | I | J | K | L | M | N |
Type I Size Code Parameters for Fleets / Subfleets
| Motorola | TT | Trunker.exe | Fleets | Subfleets | Ids |
| A | S1 | A | 128 | 4 | 16 |
| B | S2 | B | 16 | 8 | 54 |
| C | S3 | C | 8 | 8 | 128 |
| D | S4 | D | 1 | 16 | 512 |
| E | S5 | E | 64 | 4 | 32 |
| F | S6 | F | 32 | 8 | 32 |
| G | S7 | G | 32 | 4 | 64 |
| H | S8 | H | 16 | 4 | 128 |
| I | S9 | I | 8 | 4 | 256 |
| J | S10 | J | 4 | 8 | 256 |
| K | S11 | K | 2 | 16 | 256 |
| M | S12 | L | 1 | 16 | 1024 |
| O | S13 | M | 1 | 16 | 2048 |
| Q | S14 | N | 1 | 16 | 4096 |
EDACS Overview
EDACS was created by General Electric and then further engineered by Ericsson. The EDACS technology has changed numerous owners and now is currently owned by M/A Com.
EDACS is a lot similar to Motorola trunking. It provides for the same features yet has different names for them. Simulcast networks work the same yet EDACS networks, which are similar to AMSS networks, are all independent of each other but still interconnected. A radio is programmed with each system independently and selects each system based on control channel quality. Rather than have a site number a system is basically assigned a simple number to differentiate it.
Motorola uses a specific bandplan or a complicated frequency defined system to assign frequencies. EDACS uses what are called Logical Channel Numbers [LCN]. Rather than assign a frequency with a specific identifier, each frequency at a site is assigned a number between 1 through 21. When a channel announcement occurs it contains only the LCN. With this in mind each radio must be programmed with which frequency corresponds to which LCN.
Digital communications is also available for EDACS systems and exists in two different formats, AEGIS and Pro Voice. AEGIS was the first format introduced and Pro Voice was the last and current format. Neither one is APCO-25 compliant unlike Motorola’s ASTRO, which is. Also, neither AEGIS nor Pro-Voice can communicate with each other.
EDACS Talkgroups Conversions
The Uniden EDACS format: (Agency Fleet Subfleet) Using this example (586 DECIMAL = 04-092 AFS = 24a HEX): (1) 586 decimal = 01001001010 binary (talkgroups are 11-bit binary) (2) Split the binary as follows 0100 | 1001 | 010 (3) Convert each group to decimal 04 09 2 (4) Format as 04-092 The HEX translation would be: (1) 586 decimal = 01001001010 binary (2) Split binary as 010 | 0100 | 1010 (3) Convert each group to HEX 2 4 a (4) Write as 24a The BC245 can do the DECIMAL/AFS conversion internally, and the user can choose either mode of entry and display. So it won't be necessary to do this by hand. |
EDACS Fleet mapping
Establishing a fleet map structure dictates the max number of agency and fleet calls which can be assigned. Within the fleet map structure, the more agencies that are setup, the more agency calls that can be assigned. The same is true for fleet calls. To enhance each agencies flexibility, you can have different fleet and subfleet structures for each agency to suit specific radio communications requirements
A group call is addresses using a Group ID (GID). The GID is composed of 11 bits to define a total of 2048 max groups. The fleet map is structures for each agency to suit their specific requirements.
Some examples of the possible fleetmaps are shown below (similar to Motorola Fleetmaps)
| Agencies | Fleets | Subfleets |
| 2 | 32 | 32 |
| 2 | 16 | 64 |
| 2 | 8 | 128 |
| 2 | 4 | 256 |
| 4 | 32 | 16 |
| 8 | 8 | 32 |
| 8 | 16 | 16 |
| 16 | 16 | 8 |
The most common fleet map used by EDACS systems is 8 (3 bits) agencies, 16 (4 bits) fleets and 16 (4 bits) subfleets. If we take a couple of examples of group calls, you can easily see how simple the fleet structure really is.
Using a 3/4/4 structure, we can now partition the 11 bit Group ID (GID) as follows:
_ _ _ / _ _ _ / _ _ _ _
Agency Fleet Subfleet
Binary examples are shown below:
Agency 1, Fleet 1, Subfleet 1 (GID 273 Decimal)
0 0 1 / 0 0 0 1 / 0 0 0 1
Agency 1, Fleet 1, Subfleet 15 (GID 287 Decimal)
0 0 1 / 0 0 0 1 / 1 1 1 1
A group call for Agency 1, Fleet 1, Subfleet 0 (GID 272) is a Fleet group call. All subfleets in Agency 1, Fleet 1 will respond to the call. A binary representation is as follows:
0 0 1 / 0 0 0 1 / 0 0 0 0
When an EDACS radio sees the fleet call assignment (GID 272), it immediately associates Subfleet 0 as being a Fleet call for Agency 1, Fleet 1. If the radio's channel selector is on a subfleet within Agency 1, Fleet 1, the radio hears the call.
A group call for Agency 1, Fleet 0, Subfleet 0 (GID 256) represents an Agency Group call. All fleets and subfleets in Agency 1 will respond to the call. A binary representation is as follows:
0 0 1 / 0 0 0 0 / 0 0 0 0
When the radio sees the Fleet call assignment (GID 256), it will immediately associate Fleet 0, Subfleet 0 as being an Agency call for Agency 1. If the radio's channel know is on a subfleet within Agency 1, the radio will automatically hear the call on GID 256.
This type of fleet mapping ensures Agency Fleet calls under failure mode of operation (such if the Site Controller were to fail)
EDACS Misc. Information
EDACS Equipment Information
EDACS System Overview
Enhanced Digital Access Communications System (EDACS) is available in VHF, UHF, 800 and 900 frequency bands and wideband (25 kHz) and narrowband (12.5 kHz) configurations. This spectrum resource provided a springboard for the development of trunking systems. Public service radio manufactures working with Associated Public-Safety Communications Officers (APCO) developed a requirements document (APCO 16) for trunked radio systems.
EDACS provides coordinated communication between agencies and integrates all services; Dispatch, Secure Voice, Telephone and Data within a single common communication system. EDACS systems have a single control channel communicating between the system and the field radios. These configurations range from Basic EDACS to EDACS Level 4, consisting of Voted and Simulcast Systems. An EDACS Multisite Network links Systems together via a Multisite Controller (MSC) or Integrated Multisite and Console Controller (IMC).
There are two types of radio channel designations are used in EDACS: One of them is the Control Channel and the other is the Working Channel. The Control Channel is used to send digital data between sites to the radios. This data is continually transmitted to the field units. The Working Channels sends voice and data over the air.
Used for continuous data (full duplex) Inbound and Outbound 9600/4800 bits per second.
Working Channel
Up to 23 per Site
Voice and Data
Data message 9600/4800 bits per second.
Low Speed Data for updating units: Analog Calls 150 Bits per sec, Individual and scan group calls
Units will send 75Hz and 150Hz Trunked Unit Transmitting.
Control Channel GETC must be reset to bring site out of Failsoft Manual or Remote accomplished.
Failsoft sites can work in Multisite configuration less than .5 second Channel Access.
If NO Working Channel available the Call goes into Queuing an available channel.
Wide Band (25/30) kHz: 9600 baud
Narrow Band (12.5) kHz 4800 baud
9600 Baud Rate at 0.1 bit (0.01ms)
150 Baud Rate at 0.01 bit (0.06ms)
Amplitude of 0.25 dB (300-3000Hz)
Phase of 25 degrees (600-2600 Hz)
Channel Access Time: Less than 500 ms
Max ISI Time: 52 uS (Allowing for 10 uS of Jitter)
Max Site Separation: 7.8 miles (Without Timing Adjustments)
Velocity of Propagation: 3.0 X 10E8 m/s
9600 Baud Period: 104 uS
Bell Standard T1 or DS1 Grade Circuits Via: Digital Microwave - Fiber Optic - Phase Stable Analog Multiplex / Microwave
Total Number of Logical Address Schemes: 16,384 (0 to 16,383)
Logical ID uses 14 bits
Used for System Validation
LID 0: Test Unit when making Test Calls
LID < 64 for Host Computers or Mainframe
LID > 100 for Consoles
Total Number of Group Address Scheme: 0 to 2048
Each Radio has a Physical ID
20 bits Physical ID
1,048,576 possibilities
ESN
Simultaneous Broadcast by two or more transmitters located at different sites operating on the same RF Frequency. A Simulcast trunked system requires the same number of channels with a common set of RF Frequencies at each site. For this reason, alignment of simulcast systems become very important.
The ability of an FM Discriminator to lock on the incoming signal: RF Level 1 > RF Level 2 by 12 dB
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