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LATIN: 100601-1-0-O

Issue Date: 18 June 2010 Expiration Date: 18 July 2011 To: Latin America & Caribbean Countries Region Authorized Distribution Channel

From: LACR Indirect Subscriber Engineering Group Plantation, Florida, USA Subject: MOTOTRBO Repeater DMM Guidelines and Configuration

The information contained in this L.A.T.I.N. is for informational purposes only, for use by Motorola Authorized Distribution Partners under an active Distribution agreement for the product(s) and conditions specified below. This L.A.T.I.N. is intended for the exclusive use of the Entities to whom it is addressed. Any dissemination, distribution or copying is strictly prohibited. No warranty is implied or authorized.

Description: The following is an explanation of Dynamic Mixed Mode (DMM) system along with explanations of DMM repeater configurations. Please refer to the latest System Planner (6880309T12-X) for more details.

System Model and Topology: DMM is a REPEATER ONLY configuration! The repeater will dynamically switch between analog and digital modes based on the call type it receives from radios. When users are operating in DMM mode, their subscriber radios will use a pair of physical channels to be configured as: 12.5kHz channel bandwidth for digital operation and 25kHz and/or 12.5kHz channel bandwidth for analog operation. Very Important Information Follows:

If an analog radio transmits, the repeater switches to analog mode to repeat the analog call. However, the repeater only repeats analog calls that are qualified by a PL (DPL/TPL) code. These codes must be used for repeat transmissions.

Only PL (DPL/TPL) squelch types are supported for repeat mode as CSQ repeat is not supported. However, if the receive squelch type is configured to CSQ, the received audio is sent over the Rx audio accessory pin to support community repeater operation.

If a digital radio transmits, then the repeater will switch to digital

mode to repeat the digital call. The repeater can repeat one analog call at a time or it can repeat 2 digital calls at a time, one on each logical channel.

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When a repeater repeats a new digital call that starts on one of the logical channels, the repeater does not qualify any analog calls, including an emergency call, until the digital call (both the transmission and the call hang time) is over and the corresponding channel hang time has expired. Upon the expiry of channel hang timer, only then does the repeater start qualifying both analog and digital calls simultaneously. Similarly, if an analog call is being repeated, the repeater does not qualify any digital call, including digital data and emergency calls, on any of the two logical channels until the analog call is over and the corresponding hang time has expired. Analog console device(s) are supported only when the repeater has not qualified an Over the Air (OTA) digital call. Once a call type (analog or digital) has been qualified, the repeater will not try to qualify another call type until the current call is complete, including the call hang time hang and channel hang time. For digital calls, the hang time needs to be expired on both logical channels. Analog call types includes an Over-the-Air (OTA) call or any operation (PTT, pin knockdown) on the 4-wire Analog Repeater Interface (ARI) trying to access the repeater. Once a digital call has been qualified, an audible alert (channel busy tone) is generated over the speaker and Rx audio pins on the 4-wire repeater interface. If the analog console tries to key up the repeater when a digital call has been received over the air, the analog console call will be denied. The repeater notifies the console via a channel busy tone played on the 4wire-line. Note: Analog consoles do not have priority over digital voice in DMM mode. To ensure proper DMM operation, only exclusive CWID transmissions are supported in MOTOTRBO repeater operating in DMM mode, while mixed CWID is not supported in order to be compliant with the digital mode of operation. Furthermore, the exclusive CWID transmission cannot be interrupted by either OTA or repeater accessory PTT transmission.

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Since CWID transmission is uninterruptible in Dynamic Mixed Mode, it is recommended not to add PL with CWID so that analog radios do not key up during CWID transmission when their admit criteria is set to Correct PL or an equivalent. DMM main functions are: The system requires one pair of physical channels (one Tx frequency and one Rx frequency) for both analog and digital calls, one MOTOTRBO repeater, and one set of RF equipment (antenna, combiners, couplers, LNA, etc) to enable analog and digital radio users to communicate. This configuration allows the user to have a mix of legacy analog radios and the digital MOTOTRBO radios in a MOTOTRBO system. The repeater supports two independent time slots or logical channels within the 12.5kHz physical channel bandwidth while repeating digital calls. However, the repeater supports one voice path (transmit and receive) on a 25kHz or 12.5kHz channel while repeating analog calls. DMM DOES NOT support the following configurations/features: IP Site Connect configuration - This means that in DMM, the repeater can only repeat the digital calls Over-the-Air and can not send the voice/ data packets over the IP network. The status of the repeater and the control of the repeater cannot be performed from a remote PC application like RDAC-IP. RDAC over IP feature - RDAC over local USB and connections via GPIO are supported. RDAC over the network is NOT supported. Capacity Plus configuration - This means that in DMM, trunking the logical channels of multiple MOTOTRBO repeaters, as per Capacity Plus, is not supported. FCC Type-I and Type-II monitoring - Since FCC Type-I and Type-II monitoring are not supported in single site analog operation in any of the earlier MOTOTRBO releases, it is also not supported in DMM single site operation.

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Transmit Interrupt feature - The Voice Interrupt, Emergency Voice Interrupt, Remote Voice De-key, and Data Over Voice Interrupt features are presently not supported in DMM systems. Repeater Knockdown - In DMM systems, this feature is not supported during an ongoing digital transmission. PTT on a 4-wire interface - In DMM systems, this feature is not supported during a digital repeat operation. Antenna Relay In DMM systems, the antenna relay is not supported. DMM System Design Considerations: DMM is a REPEATER ONLY configuration! Dynamic Mixed Mode is a programmable channel in the repeater and this channel can be added using the CPS. Loading Considerations: A digital transmission may occupy a repeater's physical channel for twice as long as an analog transmission since there are 2 logical digital channels on each physical channel and transmissions may occur on each logical channel one after another. With a relatively small number of digital radios in DMM system, it is recommended to configure digital radios to operate on only one logical channel during migration to provide fair channel access between analog and digital transmissions. As more digital radios start replacing the analog radios, distribute some of the digital radios to use the other logical channel. It is important to note that heavy users of one category (analog or digital) will occupy the channel longer than the users in the other category when they are in a polite system configuration. It is recommended to keep digital channel hang time to the minimum, or as low as possible, to allow fair channel access between analog and digital calls. However, with a smaller channel hang time, the system access time for

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digital calls may increase due to the fact that the radios need to wake up the repeater before calls. Programming Considerations Repeater For analog repeater operation, configure the Rx and Tx squelch types as PL (TPL or DPL) in the repeater. The DMM repeater does not repeat if Rx squelch is configured as CSQ. However, if the receive squelch type is configured to CSQ, the received audio is sent over the Rx audio accessory pin for community repeater operation. Subscriber A few repeater and subscriber configuration recommendations have been laid out to ensure proper Dynamic Mixed Mode system operation. Configure the Tx and Rx squelch types as PL (TPL or DPL) in both legacy analog and MOTOTRBO radios. If Rx squelch type is configured as CSQ, the radios will unmute to digital transmission and play out digital noise. Configure the admit criteria of both analog and digital radios to be polite to each other. MOTOTRBO radio configuration recommendations are provided in the table below. For legacy analog radios, it is recommended to configure the polite rule as Busy Channel Lockout on Wrong PL code. If MOTOTRBO radios need to communicate on their digital channels with the legacy analog radios or with MOTOTRBO radios on analog channels, the digital channels can be configured to scan for analog channels by way of scanning DPL or TPL. Scanning may result in an initial audio truncation and the truncation depends on the number of scan members in the scan list. It is recommended to have a digital channel as the home channel and add the analog channels to the scan list. This is because the scanning radios can receive data messages only on the home channel. Priority sampling and channel marking CPS configurations are recommended to be disabled in a DMM system.

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To prevent loss of digital data transmission, it is recommended to configure the preamble duration as per the following recommendations: Scanning and Preamble Since data and digital signaling messages are typically shorter in duration than voice transmissions, it can be difficult for a scanning radio to detect such messages. This is especially true as the number of scan list members increases because the amount of time between a scanning radios repeated visits to a particular scan list member increases, making it less likely to be on the channel at the exact moment that the data or digital signaling message begins. Another factor is the amount of activity on each scan list member; basically, the more active each scan list member is, the more likely that the radio is suspending its scan operations to receive on each of those scan list members, further increasing the likelihood that the radio will not receive the data or digital signaling on another scan list member. To improve the likelihood of receiving data and digital signaling messages, the duration of these message types can be extended by preceding the message with special preamble signaling. The amount of preamble signaling to use can be configured into the initiating radio and the amount of preamble to use is dependent upon the number of scan list members in the target radios scan list and whether priority scan is being used. Since this added signaling increases the amount of airtime used for data and digital signaling messages, there is a trade-off between increased channel loading and increased likelihood of receiving data and digital signaling messages while scanning. Suggested guidelines for the amount of preamble duration to use with scan lists not using priority is provided in the following table.

The preamble duration should be increased when scan list members tend to carry lots of traffic or long transmissions. If no radios in the system will use the scan feature, then the amount of preamble may be set to zero.

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More of the Repeater and Subscriber CPS configuration recommendations are listed in the following tables: Repeater Configuration

Description

Channel Add a new DMM channel and program the parameters for

that channel. Repeater Type Configure for Single Site. IP Site Master or Peer

configurations are not supported in a Dynamic Mixed Mode Sytem.

SIT Timer Configure the SIT timer so that the channel hang time (SIT Group/Private/Emergency Call Hang Time) is as small as possible. This will allow analog users to get almost immediate access once a digital call has ended. Channel Hang Time = (SIT Call Hang Time) Example: When SIT = 7 seconds and Group call hang time = 5 seconds, therefore the channel hang timer = 2 seconds for that Group voice call (7-5=2) Example: When SIT = 7 seconds and Private call hang time = 4 seconds, therefore the channel hang timer = 3 seconds for that Private voice call (7-4=3)

RX/TX Squelch Configure this to TPL or DPL for non-community repeaters where the received audio is repeated OR Configure this to CSQ for community operated repeaters where the received audio is NOT repeated. Instead the audio is repeated over the RX audio accessory pin.

Strip PL Check this box to ensure that a PL is not added to CWID.

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Radio Configuration Description TX Preamble Duration This duration depends on the number of

members in the scan list. If the radios are required to scan analog channels, it is recommended that the number of analog channels be kept to a minimum.

RX Squelch Type Configure to TPL or DPL. If configured to CSQ, the radios will unmute to all Digital transmissions and Digital noise will be heard on the radios speaker.

TX Squelch Type Configure to TPL or DPL. The repeater does not repeat if there is no PL in the received signal.

Admit Criteria Configure ANALOG channel Admit Criteria to Correct PL Configure DIGIAL Admit Criteria to Channel Free.

Priority Scanning Disable Priority Scanning on all scan members in the scan list.

PL Type (In Scan list) Configure for NON-Priority so that PL decoding is required for Non-Priority scan list members (All members since Priorities were disabled in the above step)

Channel Marker (In Scan list)

Configure to be Disabled.

Talkback Check this box so the radios will talkback on the channel they received on during scan.

Tx Designated Channel Choose Selected or one of the configured scan members as needed. It is NOT recommended to configure as Last Active Channel.

Analog Hang Time Configure this value to be as small as possible so the radios can start scanning immediately

Digital Hang Time Configure to Repeaters SIT timer value + 1 second.

RSSI Threshold Adjust this value based on RF interference Note: Only certified technicians can determine if RSSI changes are required.

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Repeater Configurations:

Ensure the repeater has DMM enabled, see the following figure.

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Ensure the Repeaters SIT Timers is configured correctly, see the following example configuration :

Note: In order to accommodate the reserved hang time after each transmission, the SIT timer should always be larger than the call hang time in the repeater.

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Ensure the repeater type is set to Single Site, see the following figure:

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Example of a Repeaters DMM channel configuration, see the following figure:

Note: DMM Channel is configured for a TPL or DPL signaling.

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Example of a Subscribers Transmit Preamble Settings:

Note: This duration depends on the number of members in the scan list. If the radios are required to scan analog and digital channels, it is recommended that the number of analog channels in the scan list be kept to a minimum.

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Example of a Subscribers Digital Channel:

Note: The Admit Criteria has to be set to Channel Free.

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Example of a Subscribers Analog Channel:

Note: The Admit Criteria has to be set to Correct PL.

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Example of the Radios Scan Hang Time Timers Configuration:

Digital Hang Timer: In DMM, the repeater reserves the channel for digital calls until the end of (SIT +1) seconds. Since no analog calls will be allowed until this time has expired, it is recommended to set the Digital Hang timer to the value of the repeaters SIT timer, plus one second (Repeater Sit timer value + 1 second). Analog Hang Timer: This timer should be set as low as possible so scanning starts immediately.

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Example of a Radios Scan list Configuration:

PL Type is set to NON-PRIORITY. Talkback is Enabled Channel Marker is Disabled TX Designated Channel is Selected

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This L.A.T.I.N. is for informational purposes only. No warranty is implied or authorized.

If you have any questions concerning this LATIN, please use the Contact Us feature on the MOL website at https://www.motorola.com/businessonline.

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