RF Power Amplifiers Multiple Carrier Power Amplifiers Model: MCPA1900 & MCPA850 Operation Instruction Date: July 25, 2005 Version. 1.
RF Power Amplifiers Introduction This document presents description of the Andrew Corporation 850/1900 Band MCPA (Multi-Carrier Power Amplifier) amplifiers. The MCPA amplifier is a high power, mixed-mode RF amplifier intended to provide signal amplification and conditioning. The MCPA amplifier is compatible with GSM/EDGE and WCDMA air interfaces operating in U.S. domestic cell sites where FCC compliance is mandatory. The Cell band (869 MHz to 894 MHz) MCPA and PCS band (1.93 GHz to 1.
RF Power Amplifiers The cell amplifier has been designed to support an instantaneous bandwidth of 25 MHz. Multiple carriers may be placed within a continuous 25 MHz span and the product shall meet specified performance marks. The PCS amplifier has been designed to support an instantaneous bandwidth of 45 MHz. Multiple carriers may be placed within a continuous 45 MHz span in the PCS band and the product shall meet specified performance marks.
RF Power Amplifiers Control System: A microprocessor controller is used to control the amplifier alarm system, control environmental compensation of the amplifier, and to maintain a linearization solution for the pre-distortion circuit and the feed-forward circuit.
RF Power Amplifiers Alarm LED Fan Tray Assembly Warning LED Captive Screw Mounting Active LED Handles Tx Enable Disable Switch RS232 Debug Port Fan Tray Interface Figure 3 MSA850-135 MCPA Front Panel DC/Control/RF Input Connector 24W7 Combo D-Sub RF Output Connector Type N Figure 4 MSA850-135 Rear Panel The following table is a summary of detailed alarms within the PA Module. The alarms are mapped to front panel LED behavior, as indicated.
RF Power Amplifiers Condition (Shading shows grouping) Initial Power On, no alarms Self Test fail Normal Operation – RF enabled Normal Operation – RF disabled Fans (see note 1) High temp, Minor High temp, Critical (see note 2) RF overdrive Major (see note 3) RF Overdrive Critical (see note 4) Linearizer (see note 5) Device health and Internal Voltages Sensor fault (see note 6) Device current (see note 7) VSWR minor (see note 8) VSWR critical (see note 9) Low input voltage (<26V) Bias fault (factory only) (
RF Power Amplifiers threshold is typically 10.5 dB above rated input power (51.3 dBm output – 56 dB nominal gain). Note 5: Whenever a linearizer alarm occurs, the amplifier is shut down. Each actively tuned gain and phase adjuster has a factory nominal setting with leash limits around it. Whenever the tuning algorithm persistently requires an adjustment beyond the leash limits, a linearizer alarm is declared. Note 6: Some sensors allow fault detection because they give readings that are out of range (e.g.
RF Power Amplifiers Installation and Operation Set-Up The MCPA is easy to operate and use, requiring no special cabling since the main input/output and +27V DC @ 30A, power connections are all blind mated into a backplane. The input signals are also distributed to the amplifiers via the sub rack wiring from a front RF connector. FCC Statements: FCC ID S8L-100270MCPA & RE: FCC ID S8L-100254MCPA This devise complies with Part 2, 15 & 24 of the FCC Rules.
