Can Bus; Rfds Frequency Band And Bandwidth; Mts Lite And Mts 2 Rfds - Motorola DIMETRA MTS 4 Installation, Configuration, And Service Manual

Applicant: Motorola Solutions
230 | Radio Frequency Distribution System

CAN Bus

The intercommunication between the RFDS units (the Duplexers, Post Filters, and Cavity Combiners) and the Site
Controller is carried out through the CAN Bus at 125 kB/second. The connectors for the CAN Bus are RJ45
connectors. The CAN Bus is terminated at each end, either by the Site Controller or by an RJ45 terminator.
Each device is registered at the Site Controller (SC), which specifies the particular channel for each unit. Every 30
seconds, each unit on the CAN Bus transmits status and alarm information. Alarms are triggered when any thresholds
are exceeded, (failure alarms, software revisions, and so on). The following common information is available from
the CAN Bus: serial number, TrackID, software revisions, and the Motorola kit number. For each unit, specific
information is available, for example, voltage standing wave ratio (VSWR) for DPMs and tuning information for
Cavity Combiners.
The receive path of the Preselector or Duplexer is not connected to the CAN Bus. Because the supply voltage is
supplied from the Base Radio, the Base Radio can withstand a short or 50 ohms connection to the RX input without
the Base Radio or the Power Supply Unit (PSU) being damaged.
For more information on CAN Bus, see

RFDS Frequency Band and Bandwidth

MTS LiTE, MTS 2 and MTS 4 are available in the 350 MHz– 470 MHz range. The bandwidth of the filters is 5 MHz
and the duplex spacing is 10 MHz.
MTS 2 and MTS 4 are available in the 260 MHz– 275 MHz range. The bandwidth of the filters is 6 MHz and the
duplex spacing is 9 MHz.
MTS LiTE, MTS 2 and MTS 4 are also available in the 851 MHz – 870 MHz range. The bandwidth of the filters is 19
MHz and the duplex spacing is 45 MHz.

MTS LiTE and MTS 2 RFDS

In terms of RFDS, MTS 2 uses a low-power, cost effective RFDS placed on top of a card cage, intended for up to 2
Base Radios. For MTS LiTE, the RFDS is placed beside the card cage intended for only 1 Base Radio.
The RFDS in MTS LiTE and MTS 2 is made up of the following:
• One or two Preselectors with integrated high performance low noise amplifier (LNA). The supply voltage for the
LNA is supplied through the RX out connected to the Base Radios. The Preselector has two outlets for two Base
Radios. The dimensions of the filter are: 85 x 280 x 70 mm, excluding connectors. The antenna connectors are
DIN 7–16, the receive side is connected with QMA connectors. See the block schematic of the MTS LiTE/MTS 2
Preselector in
• One or two Duplexers rated for up to two TETRA modulated carriers. The antenna connectors are DIN 7–16, the
transmit side is connected with QN connectors. The Duplexer has an integrated digital VSWR meter. The supply
voltage for the digital VSWR meter is supplied through the CAN Bus interface. The receive side has integrated
LNA as for the Preselector and two RX outputs (QMA). The supply voltage for the LNA is supplied through the
RX ports. The filter dimensions are approximately: 170 x 280 x 70 mm excluding connectors. See the block
schematic of the MTS LiTE/MTS 2 Duplexer in
on page 239.
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Site Controller CAN Bus on page
Figure 142: Schematic Diagram of MTS LiTE / MTS 2 Preselector on page
Note: MTS LiTE supports up to one Preselector.
Equipment Type: ABZ89FC5827 / 109AB-5827
271.
Figure 144: Schematic Diagram of MTS LiTE / MTS 2 Duplexer
236.
Exhibit D2