S-band 120 kW pulse transmitter for radar and test
Empower RF Systems has released an S-band, 120 kW pulse transmitter that sets the bar for extreme high-power solid state COTS amplifiers. The Model 2236 is liquid cooled and combines the output of two six foot cabinets with each cabinet combining sixteen 2U power amplifiers. Lower and higher power versions of this amplifier are available due to the scalable, modular design.
Operating from 2800 to 3500 MHz, the flexible pulse handling capabilities of this fielded system includes 20% duty cycles with pulse widths from 200 ns to 500 µs and PRFs up to 500 kHz.
The 2236 is designed for lower total cost of ownership and higher availability than TWTs and legacy solid state implementations.
The transmitter consists of a system controller in a 3U 19-inch rack unit and a total of thirty two 2U 19-inch rack amplifier drawers with each amplifier drawer containing an integrated power supply in its 2U chassis. There is no separate system level power supply. This arrangement eliminates the risk of an RF section or single power supply failure taking the entire amplifier offline. In the event of an RF pallet or PA drawer failure, only a fractional reduction of output power is realized, and the amplifier system remains on air. A single 2U PA drawer and 3U system controller would comprise a spare system.
Each of the amplifier subsystem drawers features multiple high power GaN on SiC devices that provide wide frequency response, high gain, high peak power capability and low distortions. Exceptional performance, long-term reliability and high efficiency are achieve by employing advanced broadband RF matching networks and combining techniques, EMI/RFI filters, and all qualified components. Each drawer is a full gain PA with integrated single phase power supply and liquid cooling. It features gain and phase control and is fully hot swappable in case of failure.
The amplifier system includes a built-in control and monitoring system, with protection functions which preserve maximum output availability and reliability. The duty cycle and the pulse width protection can be selected to back off the power when any of them violates the maximum limits. The protection will act immediately and back off the output by about 10 dB and will stay in this condition until the operation returns to normal for at least 5 pulses, therefore there will be no change in the shape of the pulse after the first detected violation. This feature allows the transmitter to operate in CW with back-off of the output power at around 10 kW. Remote management and diagnostics are via Ethernet port to a LAN. It is performed remotely by a web browser or M2M (machine to machine interface) or locally by a panel computer. The control system runs an embedded OS (Linux), has a built-in non-volatile memory for factory setup
Servicing costs and technician expertise are much lower due to the Fast Field Replaceable (FFR) design. Drawers can be hot swapped (optional) or muted swapped (standard), from the front, in less than 15 minutes. The result is a system with extreme Effective MTBF. Droop correction option is available.