Aethercomm is introducing a new super broadband 20 to 2500 MHz, single module, 20 W solid-state power amplifier. The model SSPA 0.020-2.500-20 amplifier was designed and manufactured for several different platform types. The US military is transitioning to software-defined radios that cover the majority of this bandwidth. Existing systems employ two or even three amplifiers to cover the 20 to 2500 MHz bandwidth. For medium power missions, the new broadband solid-state amplifier can be a single module solution for the entire bandwidth.


Modern electronic warfare systems operate over these bands and utilize exciters that drive multiple power amplifiers to accomplish the system requirements. This new multi-octave amplifier can enable these systems to be smaller in volume and lower in DC power consumption as one amplifier can now replace two or even three existing amplifiers.

The actual applications for this amplifier are numerous. This unit may be employed in any system that requires high power, flat gain and high linearity over the full amplifier bandwidth. The amplifier could be employed in test equipment, communication systems or general lab use. The processes used in its manufacture make this RF module extremely rugged and make it useful in a ground vehicular environment, sheltered or unsheltered shipboard environment or airborne inhabited or uninhabited environment.

High Performance Over a Broad Bandwidth

This super broadband amplifier successfully covers the full 20 to 2500 MHz bandwidth with high gain, high power, an extremely flat gain response and a high OIP3 across the band. The most difficult design challenge the designers faced was capturing the low frequency response. These types of designs typically require ferrite devices to achieve the low frequency responses. This new design was ultimately able to balance the high end of the band with the low end, while achieving the required high power and flat gain.

Designed for rugged military applications, the SSPA 0.020-2.500-20 broadband amplifier operates from +28 VDC. The quiescent current from the +28 V supply is approximately 5 amps. Under drive the current will go up to approximately 6 amps. At saturated output power the efficiencies are typically 10 to 15 percent over most of the band. A listing of the RF amplifier’s performance can be found in Table 1.

The RF performance of this amplifier is exceptional for the bandwidth covered. The gain of the amplifier is 45 to 50 dB with a typical gain flatness of ±2.5 dB, and can be flattened further if required. The 1 dB compression point (P1dB) of this unit is 41 to 43 dBm over most of the band. The saturated output power (PSat) of this RF module is 42 to 44 dBm over most of the band. The measure of linearity used to characterize the amplifier was its output intercept point (OIP3). The OIP3 of this amplifier is typically 51 to 53 dBm across the majority of the band. Another important parameter of super broadband amplifiers is in-band harmonics. The Aethercomm solution has typical in-band harmonics of –20 dBc for the second- and third-harmonics at P1dB. A graphical representation of the amplifier’s performance is found in Figure 1. The typical noise figure of this unit is 8.0 dB in the small-signal region of operation. Input and output VSWR is 2.0 maximum.

The SSPA 0.020-2.500-20 amplifier offers many standard and self-protection features that make it robust in demanding environments. The unit offers over-voltage protection with under-voltage lock out. Reverse polarity protection is standard on the amplifier. The RF module is protected from an open or short circuit placed on the RF output connector via a bad cable or antenna. There is an internal DC blanking function that enables and disables the RF devices in 5000 ns maximum. This feature is employed if there is a receiver used in conjunction with the power amplifier or if a “look through” function is required in an EW jamming system. In standby mode, the amplifier draws 100 mA maximum.

The amplifier is packaged in a modular housing that is 10.0 by 12.0 inches and 1.5 inches in height. The typical weight of the amplifier is 7.5 pounds. The input and output RF connectors are SMA female type. DC and command/control functions are employed via DC feed through capacitors.

Conclusion

Aethercomm has successfully manufactured a 20 to 2500 MHz solid-state RF power amplifier capable of 10 to 20 W P1dB across the full band. The saturated output power is 15 to 30 W across the full band. This super broadband unit is currently available today in small piece quantities or for high volume manufacturing. In addition, higher output power is available. Additional information may be obtained by contacting sales@aethercomm.com.

Aethercomm Inc.,
San Marcos, CA (760) 598-4340,
www.aethercomm.com.