Powerwave Technologies 5JS0077 Users manual

PRELIMINARY

EHP19

Integrated Power Transceiver

Installation and
Service Manual

044-05210 Rev. A

September 2005

© 2005 Powerwave Technologies Incorporated. All rights reserved.

Powerwave Technologies, and the Powerwave logo are registered trademarks.

This Powerwave product is intended only for installation in a RESTRICTED ACCESS LOCATION.

This Powerwave product is designed to operate within the normal operating (typical operating) ranges
or conditions specified in this document. Operation of this equipment beyond the specified ranges in
this document may cause:

• spurious emissions that violate regulatory requirements.

• the equipment to be automatically removed from service when maximum thresholds are exceeded.

• the equipment to not perform in accordance with its specifications.

It is the responsibility of the operator to ensure this equipment is properly installed and operated within
Powerwave operating specifications to obtain proper performance from the equipment and to comply
with regulatory requirements.

Warnings, Cautions, and Notes

Warnings, Cautions, and Notes are found throughout this manual where applicable. The associated
icons are used to quickly identify a potential condition that could result in the consequences described
below if precautions are not taken. Notes clarify and provide additional information to assist the user.

WARNING: This warning symbol means danger. You are in a situation that could cause
bodily injury or death. Before working on any equipment, be aware of the hazards involved
with electrical and RF circuits and be familiar with standard practices for preventing
accidents.

CAUTION: The caution symbol means reader be careful. In this situation, the user might do
something that could result in equipment damage or loss of data.

NOTE

044-05205 Rev. A i

NOTE: The note symbol means reader take note. Notes contain helpful suggestions or
references to material not covered in this document. Procedures are not contained in notes.

Revision Record

Revision Letter Date of Change Reason for Change

Rev. A September, 2005 Preliminary Release

ii 044-05205 Rev. A

1.1 Introduction

This manual contains information and procedures for the installation, operation, and maintenance of
the EHP19 Integrated Power Transceiver (IPT).

1.2 Scope of Manual

This manual is intended for use by service technicians familiar with similar types of equipment. It
contains service information required for the equipment described and is current as of the printing
date. Changes which occur after the printing date may be incorporated by a complete manual revision
or alternatively as additions.

The manual is organized into the following chapters:

• Chapter 1 - Product Description

• Chapter 2 - Installation

• Chapter 3 - Operation

Chapter 1

Product Description

• Chapter 4 - Maintenance

• Chapter 5 - Specifications and Drawings

1.3 Functional Description

The IPT is a high efficiency RF single channel power amplifier with an internal analog pre-distorter for
use with the Radio Base Station (RBS) digital pre-distorter system for RF output linearity. The IPT has
an operational bandwidth of 60 MHz from 1930 MHz to 1990 MHz producing a typical output of 60.2
watts (47.8 dBm). The IPT is shown in
the IPT are listed in Chapter 5.

1.3.1 RF Interface

The IPT RF interfaces consist of the TX OUT port located on the top of the IPT front panel and the
RX0 and RX1 ports located on the bottom of the IPT front panel.

1.3.2 Main Transceiver

The following circuits are part of the main transceiver section.

1.3.2.1 Customer Interface/CPRI Input

The incoming serial data stream from the customer interface (DRIC) front panel connector is applied
to a Serialiser-Deserialiser (SerDes), converted into a parallel format and decoded. The customer
interface also includes processing of the frame alignment, byte alignment and chip alignment,
including delay adjustment. A clock acts as the frequency reference for the entire transmitter. The
clock is extracted from the incoming signal using a phase locked loop (PLL). There are two outputs

Figure 1-1. Detailed functional and physical specifications for

044-05210 Rev. A 1-1

Functional Description

from this block: control data and signal data. The control data determines parameters such as
channel frequencies, signal ramp-up/ramp down and transmit power level. These functions are
implemented in a Field Programmable Gate Array (FPGA).

1.3.2.2 Digital Up Converter (DUC)

The DUC modulates individual symbol streams from the signal data stream on to baseband carriers
and applies root-raised cosine channel filtering. This function is implemented on an Application­Specific Standard Product (ASSP).

1.3.2.3 Crest Factor Reduction (CFR)

The CFR function is implemented in the FPGA. The CPR varies the DUC signals to reduce the peak­to average power of the transmit signal to allow the P-Mod to operate with higher efficiency ensuring
the transmit signals stay in the occupied bandwidth/spectral mask limits.

1.3.2.4 D ata Interpolation (INT)

The interpolation function, which is implemented in the FPGA, changes the sampling rate up to 92.16
Msps.

1.3.2.5 Digital Predistortion (DPD)

The DPD function, which uses an ASSP DPD engine, and a Digital Signal Processor (DSP),
processes the forward path signal to compensate for the non-linearities in the forward path. The DPD
function ensures that the transmitter operates at the correct power level over variations in supply
voltage, load impedance, temperature and aging.

The DPD function also provides compensation for imperfections in the AUC such as differential delay,
I-Q amplitude and phase balance and DC offset/carr ie r leaka ge. the lin eari sa tion lock func tio n
monitors the operation of the signal and turns off the transmitter if the system is not functioning
correctly. The digital output signal from the DPD engine is converted back to an analog signal in a
high-speed digital-to-analogue converter (DAC).

1.3.2.6 Analog Up Converter (AUC)

The AUC uses a direct-conversion architecture (I-Q modulator) to transform the I-Q baseband signals
from the DPD up to the operating RF frequency.

1.3.2.7 Observation Path (OBS)

The OBS act as a high performance radio receiver tuned to the RF transmit frequency. The OBS
converts the sampled RF transmit signal to a VHF intermediate frequency where it is sampled by a
high-speed analogue-to-digital converter (ADC). The output of the ADC is fed to the DPD block,
compared with the drive signal and then used to update the parameters in the DPD algorithms
running on the DSP .

1.3.2.8 Clock Module

The FPGA high-speed serial interface (SerDes) extracts a timing clock from the incoming data
stream, the transmit frequency stability depends on the accuracy of the incoming input signal. The
recovered clock is used to synchronize a crystal oscillator used as a clean frequency reference for the
timing functions on the TRx board (RF LOs, DAC and ADC clocks, Tx, Rx and lineariser signal
processing clocks).

The reference is used as a direct reference for the RL local oscillators. Except for the digital clocks,
the reference is passed to a PLL VCO, which is then subdivided. All RF PLLs include lock-detect
signals to allow the transmitter to be turned off if there is a fault with a PLL.

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Functional Description

FRONT

Figure 1-1 Integrated Power Transceiver Front and Rear Isometric View

1.3.3 Power Module

The P-Mod is a multi-stage amplifier, which amplifies the low level signal from the AUC up to the RF
output power level of +47.8 dBm (60.25 W). The P-Mod consists of a two-stage pre-driver, a driver
amplifier and an output stage. The bias currents are electronically calibrated during factory test and
bias setting and temperature compensation are controlled by a master control unit on the P-Mod
PCB. The P-Mod also includes a directional coupler, which allows a sample of the transmit signal to
be fed to the observation path and an isolator, which protects the P-Mod from damage or potential
oscillation under adverse RF load conditions. An RF switch allows either the observation signal or the
reflected power from the antenna connector, measured at the third port of the isolator, to be passed to
the TRx

1.3.4 Front Panel

The front panel contains a RESET switch and four status and alarm LEDs.

REAR

044-05210 Rev. A 1-3

Functional Description

1.3.5 Operational States

The IPT has three operational states: Operational, Disabled and Not Ready.
The IPT remains in the Not Ready state during start-up until all parameters are met for the IPT to

become operational.
The IPT is normally in the Operational state: no faults are present, the IPT internal temperature is

within limits, appropriate DC power is applied, and the IPT is producing RF output. The green
operational (O) LED on the Man Machine Interface is lit.

The Disabled state is ordered from the RBS (if there is a fault in the IPT or in other RBS units) or
entered automatically when a critical hardware error is detected by the IPT. The Disabled state
causes the IPT to shut down, but it can be enabled by the RBS if the fault is cleared.

1.3.6 State Transitions

The IPT has five state transitions: Reset, Status OK, Alarm, Disable, and Enable.
Reset initiates the Not Ready state. This state is entered when power is initially applied to the IPT or

from a dedicated reset signal from the RBS to the IPT.
Status OK is entered from the Not Ready state and initiates the Operational state when commanded

by the IPT
Alarm initiates the Disabled state from the Operational state if the IPT detects a hardware or

temperature fault. The RBS reads the potential fault cause for fault logging.
Disable is ordered from the RBS to force the IPT to go to the Disabled state and shut down. Power on

of the IPT after a Disable can only be ordered by the RBS through a RESET command.
Enable is ordered from the RBS to power on the IPT after it has been disabled. The IPT enters the

Operational state after checking status and temperatures and re-perform start-up if required.

1.3.7 DC Power (DC)

DC power (-48 Vdc nominal) is supplied by the RBS to the IPT through the rear mounted connector.
Refer to

Table 1-1 for a description of the DC connector inputs.

Pins Signal Name Description

1,2 GND (-48V_RTN) DC plus (isolated from amplifier chassis)

3,4 -48V DC minus (isolated from amplifier chassis)

5,6 GND (NC) Not connected

1.3.7.1 Power Supply

The power supply assembly contains two subassemblies. The DC/DC converter produces regulated
+28 Vdc, +9 Vdc and +6.5 Vdc from the -48 Vdc supply for the IPT internal supply. The low voltage
supply uses the +6.5 Vdc from the DC/DC converter to provide regulated 3.3 Vdc, 1.8 Vdc and 1.5
Vdc reference level supplies.

Table 1-1 DC Power Connections

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