SSPA: Solid State Power Amplifier
The Solid State Power Amplifier has been designed for use in the most demanding applications including Airborne Radars, Missiles and Communication systems. The SSPA takes advantage of today’s cutting edge technologies in both design and manufacturing resulting in a high reliability, high performance and cost effective alternative to the Traveling Wave Tube (TWT).
Herley’s Solid State Power Amplifier family includes both X-Band and Ku-Band products offering peak power outputs up to 400 Watts using proven and cost effective GaAs power devices. The flexible SSPA design can be extended to adjacent frequency bands requiring only a short development time and at relatively low risk.
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.
The RF input to the SSPA (as described in the above block diagram 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 in the event of a failure. 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 insures that any contribution of phase noise and spurious signals are significantly reduced at the RF output. In addition, for redundancy purposes, the PSU is comprised of two identical and independent sections.
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 Solid State Power Amplifier 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.
PERFORMANCE CHARACTERISTICS
|
Model |
SPA-X1-400 |
SPA-X2-100 |
SPA-KU1-400 |
SPA-KU2-100 |
| Frequency Range (GHz) |
8.5 to 10.9 |
8.5 to 10.9 | 13.5 to 16.8
or 14.5 to 17.0 |
13.5 to 16.8
or 14.5 to 17.0 |
| Bandwidth, max (MHz) |
400 |
800 |
1,000 |
500 |
| Peak Saturated Output Power, min (W) |
400 |
100 |
400 |
100 |
| Average Output Power (W) |
100 |
25 |
100 |
25 |
| Load VSWR, max |
2:1 |
2:1 |
2:1 |
2:1 |
| Input RF Drive (dBm) (1) |
23 ± 1 dB |
-1 ± 5 dBm |
10 ± 1 dB |
12 ± 1 dB |
| Large Signal Gain, min (dB) |
36 |
52 |
49 |
41 |
| Pulse Width (μs) |
0.2 – 15 |
0.4 – 256 |
0.5 – 25 |
0.5 – 45 |
| Duty Cycle, max (%) |
25 |
25 |
25 |
25 |
| PRF (kHz) |
2 – 240 |
1 – 15 |
2 – 600 |
2 – 320 |
| Input Supply Voltage (V) |
30 to 60 |
18 to 32 |
18 to 32 |
30 to 60 |
| Current, max (Amp) |
28 |
8 |
30 |
10 |
| Efficiency, min (%) |
17 |
17 |
15 |
15 |
| RF Input Connector |
SMA |
|||
| RF Output Connector |
TNC |
|||
| Operating Temperature Range (°C) |
-40 to +85 |
|||
| Environmental Specifications |
Per airborne applications |
|||
| MTBF, min (Hours) |
12,000 |
25,000 |
12,000 |
25,000 |
| Dimensions, approx. mm (inches) | 280 x 140 x75
(11 x 5.5 x 2.9) |
229 x 178 x 30.5
(9 x 7 x 1.2) |
280 x 140 x 75
(11 x 5.5 x 2.9) |
229 x 178 x 30.5
(9 x 7 x 1.2) |
| Graceful Degradation |
Embedded |
|||
| Switching Power Supply |
Ultra quiet, non-synchronized architecture |
|||
