Westell Inc. CSI-DSP85-U7C ユーザーズマニュアル
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The repeater uses a single down-conversion/up-conversion scheme. There are multiple RF amplifier stages prior to each down-converting
mixer. The down-converting mixers are followed by a single IF amplifier. A Digital Signal Processor block then processes the resultant digitized
IF signal that was previously generated by an Analog-to-Digital Converter. The processed (filtered) digital signal is fed to a Digital-to-Analog
converter and then up-converted to RF. A driver amplifier and a final power amplifier make up the final gain stages before application to the
diplexer. The maximum total system gain (diplexer input to diplexer output) is nominally 85 dB for either the downlink or the uplink paths with
both links having independent manual and automatic gain controls (AGC).
mixer. The down-converting mixers are followed by a single IF amplifier. A Digital Signal Processor block then processes the resultant digitized
IF signal that was previously generated by an Analog-to-Digital Converter. The processed (filtered) digital signal is fed to a Digital-to-Analog
converter and then up-converted to RF. A driver amplifier and a final power amplifier make up the final gain stages before application to the
diplexer. The maximum total system gain (diplexer input to diplexer output) is nominally 85 dB for either the downlink or the uplink paths with
both links having independent manual and automatic gain controls (AGC).
AGC reacts to analog power detection on both the input and output of the uplink and downlink RF chains. A control algorithm continu-
ously monitors these detected values and dynamically adjusts various gain stages such that the net system gain value, entered
manually, is maintained without either exceeding FCC parameters or overdriving the A/D converters.
ously monitors these detected values and dynamically adjusts various gain stages such that the net system gain value, entered
manually, is maintained without either exceeding FCC parameters or overdriving the A/D converters.
Circuit Operational Description
Functional Block Diagram
Upon detection of oscillation the unit will shut down. After a “short duration” of 30 seconds the unit will attempt normal operation. If no continued
oscillation is occurring the unit will stay on. However, if oscillation is still occurring, the repeater will remain shut down and retry 1 additional time in
the “short duration” loop. If after these two “short duration” retries, the oscillation is still detected, it will turn off again and wait a “long duration” period
of 10 minutes. If after 6 “long duration” retries, oscillation continues, the unit will go into a “disable duration” of 24 hours. It will continue in the “disable
duration” loop and retry every 24 hours.
oscillation is occurring the unit will stay on. However, if oscillation is still occurring, the repeater will remain shut down and retry 1 additional time in
the “short duration” loop. If after these two “short duration” retries, the oscillation is still detected, it will turn off again and wait a “long duration” period
of 10 minutes. If after 6 “long duration” retries, oscillation continues, the unit will go into a “disable duration” of 24 hours. It will continue in the “disable
duration” loop and retry every 24 hours.
LEDs on the front panel display provide immediate visual indications of the unit’s primary power and major or minor alarm status. The
repeater features automatic shutdown protection, as a safety measure, should excessive drive be applied to the input or an oscillation
condition occur. When in a protected mode, a control algorithm determines the appropriate method of recovery to a normal, previously
defined state, or maintains the protection until manually reset. If recovery has been established, the associated LED(s) will either be
extinguished or available to be reset. The events
that trigger the error will be saved in the event log.
repeater features automatic shutdown protection, as a safety measure, should excessive drive be applied to the input or an oscillation
condition occur. When in a protected mode, a control algorithm determines the appropriate method of recovery to a normal, previously
defined state, or maintains the protection until manually reset. If recovery has been established, the associated LED(s) will either be
extinguished or available to be reset. The events
that trigger the error will be saved in the event log.
Indoor Antennas continued
3.
To determine the quantity and locations of indoor antennas, use an appropriate phone's signal meter to determine areas
of weak signals. These are the approximate areas where indoor antennas may be needed. Also be aware the signal from
an indoor antenna, in most cases, can be expected to penetrate about two standard office sheetrock type walls to reach
users. After two walls or if the walls are made of other materials, it may be necessary to split the available signal and add
more antennas.
an indoor antenna, in most cases, can be expected to penetrate about two standard office sheetrock type walls to reach
users. After two walls or if the walls are made of other materials, it may be necessary to split the available signal and add
more antennas.