A 125 W Pulsed Ku-band Power Amplifier
Advanced Ku-band radar systems used in airborne military platforms need reliable, small size and weight, high power amplifiers. Sophia Wireless Inc. has developed a solid-state power amplifier, model MPC8-1520, which meets these requirements. Its key features include:
- Operating frequency: 16 to 17 GHz
- Internally pulsed RF
- DC storage capacitor bank
- Monitor and control processor
- Forward/reverse power monitor
- Bias/thermal protection sensors
The MPC8-1520 solid-state power amplifier provides an unparalleled size, weight and power combination. The SSPA features 125 W of power, 250 ns DC switching, 47000 mF capacitive DC storage, 45 dB gain with temperature compensation, forward and reverse power monitor with RS422 readout and a monitor and control processor, including bias sequencing control. The features and options are ideal for advanced Ku-band radar systems in military airborne platforms such as terrain-following and multi-mode radar systems, as well as navigation systems. The amplifier size is 11.1" × 4.5" × 3.1" and its weight is less than 5.1 lbs in its indoor configuration.
The MPC8-1520 solid-state power amplifier provides advanced radar systems with 125 W of RF power while the RF output power noise level during off periods is –172 dBm/Hz. The 250 ns DC switch (TTL controlled with a coaxial trigger) and the internal 47000 mF capacitor bank reduces the thermal management requirements and enables excellent power efficiency. A temperature compensation circuit minimizes gain and power variations. A forward and reverse power monitor simplifies the system power settings and reverse power protection. The safety controls include thermal and bias protection sensors to ensure reliable performance from initial system integration to harsh field environments. The specifications of the MPC8-1520 solid-state power amplifier are given in Table 1.
The output power of the amplifier as a function of frequency is shown in Figure 1. An example of the pulse rise and fall times is shown in Figure 2. The level of non-harmonics related spurious is less than –60 dBc, as shown in Figure 3.
Monitor and Control Functions
The monitor and control processor interfaces with a host computer. All voltage, current, power and temperature sensors are read through this interface, including forward and reverse power monitoring. The RS422 port communications run at 9600 or 38400 baud, 8-bit word, no parity and 1 stop bit.
The MPC8-1520 solid-state power amplifier comes in two configurations. An indoor, module-based component, as shown in the photograph, and an outdoor, system-based enclosure with integrated cooling. The specifications for the outdoor unit are identical to the ones shown for the indoor unit, except for the DC power parameters, which are +28 V DC, 235 W at 20 percent duty cycle, and the operating temperature range, which is –40° to +50°C ambient temperature. The size of the outdoor unit is 10.3" × 7.5" × 5.5" and its weight is less than 15 lbs. Additional options include AC/DC power supplies.
Sophia Wireless Inc.,