G-Way Microwave / G-Wave CELLAB25W90 사용자 설명서
BDA OVERVIEW:
The BDA assembly extends the coverage area of radio communications in buildings and RF
shielded environments.
The unit features low noise figure and wide dynamic range. It is based on a duplexed path
configuration with sharp out of band attenuation allowing improved isolation between the
receiving and transmitting paths.
The BDA supports modulation types CDMA and GSM.
BDA CIRCUIT DESCRIPTION:
Refer to figure 1 for the following discussion.
The BDA Downlink path receives RF signals from the base station and amplifies and
transmits them to the subscriber. The BDA Uplink path receives RF signals from the
subscriber and amplifies and transmits them to the base station. The Uplink and Downlink
occupy two distinct frequency bands. For example, the CELLAB frequency bands are as
follows: 824-849 MHz for the Uplink and 869-894 MHz for the Downlink. Two diplexers
isolate the paths and route each signal to the proper amplifying channel.
A selectable Automatic Level Control (ALC) allows for output power limiting. A Manual
Gain Control (MGC) provides continuous control of amplifier gain. The use of these controls
is covered in the “OPERATION” section, later in this document.
The BDA Downlink path receives RF signals from the base station and amplifies and
transmits them to the subscriber. The BDA Uplink path receives RF signals from the
subscriber and amplifies and transmits them to the base station. The Uplink and Downlink
occupy two distinct frequency bands. For example, the CELLAB frequency bands are as
follows: 824-849 MHz for the Uplink and 869-894 MHz for the Downlink. Two diplexers
isolate the paths and route each signal to the proper amplifying channel.
A selectable Automatic Level Control (ALC) allows for output power limiting. A Manual
Gain Control (MGC) provides continuous control of amplifier gain. The use of these controls
is covered in the “OPERATION” section, later in this document.
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