Configure operating RF power level as
required for application and mission
Extremely Low MTTR
Less than 3 minutes for module replacement
Intelligent, Ultra-High Efficiency Power Supply
Single Module Failure Compensation Feature
Output Frequency: 7.9 - 8.4 GHz
Output Power: 1072W @P1dB
Completely modular solid-state power amplifier systems for world-wide satellite communications.
Satellite communications providers face significant risk
when the link to a satellite is disrupted. Critical applications
go offline, customers lose confidence, and revenue is lost
as providers scramble to recover the link. Thus, most
satellite earth stations employ brute-force redundancy, i.e.
two of everything, to reduce the risk, but at significant cost
and increased complexity. When the final amplifier stage
was a single tube and thus a single point failure, having a
second amplifier immediately available was a pragmatic
solution. However, with the demonstrated viability and
practicality of solid-state amplifiers, non-brute-force
redundancy solutions offer significant cost and
ModuMAX Power Options
Solid-state power amplifiers (SSPAs) consist of multiple
transistors in parallel, and consequently contain built-in
redundancy. Because of forward thinking design, including
multiple parallel RF modules, power supplies and cooling
fans, General Dynamics ModuMAX SSPAs are extremely
reliable and fault-tolerant. With the ModuMAX series, one
fault-tolerant SSPA can replace two conventionally designed
high power amplifiers yielding significant installation
savings and reduced operating costs.
A ModuMAX SSPA combines the RF output power from
eight identical, fully interchangeable RF plug-in modules
(16 in a phase-combined system) to obtain the rated power
capacity. These amplifier modules can be individually
turned on or off via either local or remote control.
Installations can exploit this feature of the ModuMAX
SSPA to reduce prime power consumption during times
when the required RF output power is lower than the
maximum linear power capacity of the amplifier.
Additionally, the amplifier modules can also be employed
in a redundancy configuration where, in the event of a
fault occurring in the online modules, spare modules can
be brought on line rapidly via M&C. Configurable power,
the ability to adjust the number of enabled modules to
match the system output power requirements or configure
the modules in a redundant array, is a key feature of the
Configurable power is implemented by determining the
minimum number of modules that must be enabled to
provide the required RF output power. To use configurable
power, determine how many RF modules must be on line
to meet the required power while leaving the remaining
modules offline. Any modules not needed to support the
system traffic load are deactivated, either locally or via one
of the remote interfaces. When the system is operating, the
remote M&C system monitors the ModuMAX for faults. If
the M&C system detects a fault in an enabled amplifier
module, it immediately enables one of the deactivated
modules to compensate for the loss. No minimum warmup
time is required; the amplifier modules become
functional immediately upon enabling.
Configurable power allows prime power consumption to
be significantly reduced by deactivating modules while still
meeting the system RF power requirements. While power
consumption is approximately proportional to the number
of enabled modules, RF output capacity decays as shown
in Table 1.
ModuMAX SSPAs can also be phase-combined in a single
rack utilizing a fixed (hybrid) or variable (VPC) phase
combining system. The VPC system affords the operator
the flexibility to configure the system for operation using
either ModuMAX SSPA individually (single mode), or
using both simultaneously (phase-combined mode) to
nearly double the system output power. A ModuMAX
system based on a VPC has a total of 16 RF modules (8 in
each of 2 RF units), together with power supplies and the
VPC sub-system contained in a single rack.
RF Plug-In Modules
The RF plug-in modules are conveniently accessible from
the front panel. Summary module status is visually
indicated by a multicolor indicator on each module with
detailed information available at the control panel display.
Failure of a single module causes a drop of approximately
1.2 dB in output power—without the momentary loss of
signal caused by redundant switchover systems (Table 1).
Defective RF modules can be hot-swapped while the SSPA
continues to operate. Since they contain only a fraction of
the RF power transistors in the SSPA, spare RF modules
Easy to Operate and Maintain
ModuMAX SSPAs are designed to be easy to operate and
maintain. All features can be fully remote controlled
through standard RS-232/-422/-485 and network interfaces.
For quick and easy manual access, the most commonly
used controls are located on the front panel.
Most maintenance can be performed safely while the
SSPA continues to operate. Any of the eight fans in the aircooling
system can be easily removed and replaced,
without ever taking the SSPA off-line. Even the power
supply modules are redundant and hot swappable.
A ModuMAX system is easily expandable. Phase-combine
two SSPAs for double the power output using only 61.25"
(35 RU) of rack space (High power systems with two PS
chassis per RF unit require 71.75" [41 RU]). With 16 phase
combined RF modules, one failed module causes only
about 0.6 dB drop in output power.
Global EMC and Safety Compatibility
ModuMAX SSPA systems are certified to
applicable EU EMI/EMC and safety standards.
ModuMAX also incorporates redundancy into its integral
forced-air cooling system. Sufficient cooling margin is built
into the design to tolerate the loss of one cooling fan. Fans
are monitored for rotational speed, and failure of a fan is
indicated on the control panel display. In the event of a fan
failure, the SSPA can continue to operate until a replacement
is installed. The air cooling system utilizes separate
rear panel air intake and exhaust ducts and can be vented
either outdoors or into the room.
For most systems, operating power is supplied by three
identical plug-in power supply modules in a rack-mount
chassis; higher output systems require six modules (two
PS chassis) per RF unit for full redundancy. If a module
fails, the remaining ones can supply 100% of the required
load current and the defective module can be hot-swapped
ModuMAX SSPAs can be connected to 120/208 Vac or
230/400 Vac three-phase sources, or to single-phase
180–264 Vac, supporting installation worldwide.