User's Manual

EMS Wireless Operator’s Manual

MirrorCell II CDM 812, CDM1912 Series

608112-1, Rev C

7.4 Power Supply Module

The power supply is designed for an input voltage of 120 VAC, 200-260 VAC, or +24

VDC, depending on the option. A surge suppression filter is included for voltage

transient protection on the A/C powered models.

7.5 Duplexer Filters

The uplink and downlink RF signals are separated and combined with duplexers

operating in the appropriate frequency bands. The duplexers are constructed with

comb-line cavity bandpass filters, which provide excellent isolation against out-of-band

signals.

7.6 Status and Control Module

The status and control module, contained within the channelizer, enables monitoring

and control of the repeater. This module determines the status of the Channelizer and

identifies failure conditions. When a failure condition is identified, an alarm is issued.

When this occurs, the module sends a message to a PC over a serial data link

(modem). Also, the optional MUM software program, which is installed on a remote

computer, can monitor these alarms, and query the repeater on a pre-determined

schedule.

7.7 Automatic Software-Driven Gain Control

A key feature of the MirrorCell



II repeater is the automatic software-driven gain

control, or more simply, Automatic Set-up. This allows “plug and play” operation with

little or no user intervention. When Automatic Set-up is initialized, built-in software

adjusts the internal attenuators in the uplink and downlink signal paths within the

Channelizer module. Note that the UL and DL gains are generally equal to ensure a

balanced path, unless the user manually changes them or the uplink signal is too high.

For most applications, the automatic software sequence will set an appropriate gain

value without manual intervention.

The following software sequence is used:

 The repeater gain and attenuator settings can be reset by using the ‘RESTART’

software command, as described in section 4. This re-starts the software

sequence and initiates Automatic Set-up.