Comtech EF Data HPOD - Manual (Page 20)

HPOD C-, X-, Ku-Band High-Power Outdoor Amplifier MN/HPOD.IOM
Introduction Revision 8
1–2
1.1.1 Features
The HPOD SSPA base unit provides features that are typically offered as options elsewhere. Its
features include temperature compensation, sample ports, power monitor, field-replaceable
power factor-corrected power supply, and full remote monitor and control capabilities. Higher
power is available through the use of CEFD 1:1 and 1:2 phase combining kits.
• Solid-State Advantage: Each HPOD is constructed with highly reliable gallium arsenide
(GaAs) FETs. With third order intermodulation products from 4 dB to 6 dB better than TWTA
ratings, the HPOD replaces TWTAs with saturated power levels of up to twice the HPOD’s
rated output. The HPODs also provide a mean time between failures (MTBF) that is 4 to 5
times greater than the typical TWTA MTBF.
• Field-Replaceable Power Supply: Recognizing that the MTBF limiting factor for almost all
electronic equipment is the power supply, the HPOD provides for easy field replacement.
Simply disconnect the AC mains, release the captive fasteners, and remove the supply from
the SSPA module.
• Built-in Redundancy Controller: Each HPOD has the ability to function as a 1+1 (one backup
for one primary) and 1+2 (one backup for two primaries) redundancy controller in the
backup mode. The optional redundancy configuration is implemented by attaching a ganged
waveguide/coax transfer switch(es) to the input and output connectors of the amplifiers
with a combination coaxial cable and waveguide kit. When the backup SSPA is commanded
into the controller mode, it monitors the online SSPA(s) for faults. A faulted online unit may
be disconnected and replaced without affecting the online power amplifier.
• Phase Combining: Comtech EF Data’s phase-combined systems allow the outputs of two
amplifiers to be summed together. A “normal” 1:1 system using 300W amplifiers provides
300W of output power (the offline unit’s capabilities are unusable). The same amplifiers in a
1:1 phase-combined system provide 600W of output power in normal operation, and a “soft
failure” state of 300W. If no degradation on failure can be accommodated, a third amplifier
can be added to form a 1:2 phase-combined system.
• Optional “Smart BUC” Functionality: Comtech EF Data’s unique approach to L-Band/RF
frequency conversions eliminates DC and 10 MHz from the input coax. This simplifies
redundancy and multi-carrier operation. It offers full 13.75 GHz to 14.5 GHz Ku-Band
coverage and supports industry standard FSK modem/BUC communications. The optional
BUC can lock to an external or internal reference oscillator.
1.2 Functional Description
Each HPOD consists of a CEFD SSPA module with a field replaceable power supply, a field
replaceable fan assembly, and the Monitor/Control Processor (MCP). The amplifier features a
Comtech EF Data low loss combining technique and MCP based temperature versus gain
compensation.