Kratos – Solid State Power Amplifers (SSPAs)

KRATOS General Microwave offers a broad range of High Power Amplifiers for both Military and Commercial applications extending over the L-Band to Ku Band Frequency Range.

Our SSPA’s are based on legacy LD-MOS, GaAs and WBG GaN technology. In this catalog, a wide range of custom designed SSPAs is listed for various applications.

TYPICAL APPLICATIONS

1. RADAR Systems
2. ECM and COMJAM
3. Data-Links for Air Born Applications
4. Test Systems
5. Special applications

MAIN FEATURES

1. L-Band up to Ku-bands.
2. Power levels up to 1 Kw Pulsed.
3. Operating in Class A and AB.
4. Utilizing Solid state technology such as LDMOS, GaAs, GaN on Sic and GaN MMICs.
5. Supports wide range of modulations such as LFM, and various digital modulations.
6. Remote Control options of RS 232, RS422 or ETHERNET.

PA PROTECTION and MONITORING

Special measures are implemented to Protect the Power Amplifiers from the following conditions and to monitor them (at the system level):

1. Over Temperature Alarm and Protection.
2. Open/Short Load Alarm and Protection.
3. Forward Power Monitor.
4. Reflected Power Monitor.

CUSTOM PA PRODUCTS

Most of our PA products are for custom high performance applications.

SOLID STATE POWER AMPLIFIER (SSPA)

The Solid State Power Amplifier (SSPA) product line was designed for use in the most demanding applications, including Airborne, Missile, Radars and Communications. Out SSPAs design is based on cutting edge GaN technology and various types of architectures. As a result, these SSPAs provide high efficiency, high power levels and small footprint. Our SSPAs are an alternatives to applications that currently are using Traveling Wave Tube (TWT) Amplifiers. All SSPAs are designed using the Power Summation concept (see Fig.1) which provides a graceful degradation capability not found in TWTs and critical to mission completion.

The SSPA product line supports both X and KU Band applications with bandwidth of 10% typically, offering peak power outputs up to 400 Watts. Successful SSPA designs have utilized Gallium Arsenide or Gallium Nitride power devices, depending upon which was better suited for the application. The flexibility of the SSPA design provides the ability to extend to adjacent frequency bands requiring only a short development time at a very low risk.

The RF input to the SSPA is pre-amplified and split into several parallel symmetric branches. Each branch includes a power amplifier section (PA). This distributed design of the SSPA results in built in redundancy and graceful degradation of output power should any individual PA section fail. Each branch includes a current sense alarm indication which is monitored and fed to the SSPA controller. The amplified outputs of all the symmetric branches are summed up in a passive combing network which routes the resultant high power to the output of the SSPA.

A compact and highly efficient switching Power Supply Unit (PSU) is built into the SSPA. This state-of-the-art PSU design ensures that any contribution of phase noise and spurious signals are significantly reduced at the RF output. The SSPA control section includes a Modulator which switches the DC lines of the individual PA sections On/Off to achieve the required Pulse Width, Pulse Repetition Interval and Duty Cycle. The SSPA Monitoring section includes Built-in-Test capability which receives indications from critical internal subassemblies, including the PA sections, thereby constantly monitoring the condition of the SSPA.

Most of our SSPA designs are custom designed, deriving from Customer specifications for a specific applications such as Missile Seekers and Airborne Radars. In addition to custom SSPAs we have a range of catalog SSPAs.