Spaceborne X-Band Solid State Power Amplifier

Highly Efficient and Reliable Power Amplifier and Power Converter

General Dynamics’ space-qualified, X-Band Solid State Power Amplifier (SSPA) operates over the frequency range of 7.8 to 8.8 GHz. The RF amplifier design is based on GaAs power MMIC technology providing high efficiency, high reliability, small size and low mass. Included in the unit is a DC-DC power converter and regulator, specifically designed for the SSPA utilizing synchronous rectifier technology to maximize power conversion efficiency. General Dynamics flight heritage includes both Mars Exploration Rovers and the Mars Curiosity rover. It will also be used on the Mars 2020 rover.

  • High efficiency (28%)
  • GaAs MMIC technology
  • Small size and mass
  • S-level parts
  • Covers deep-space and near earth frequency bands

Features

The X-Band Solid State Power Amplifier (SSPA) is designed for use as a companion unit to General Dynamics’ Small Deep Space Transponder (SDST), or it can be used as a stand-alone power amplifier. As shown in the figure in the datasheet, the SSPA is designed to supply telemetry signals that can be connected directly to the SDST to make a complete transmitter/ receiver with a single MIL-STD-1553B data interface. The SSPA also provides a full complement of analog telemetry signals, as well as direct access to selected functions for monitoring during subsystem and spacecraft ground testing. The SSPA operates in compression to maximize efficiency for constant envelope modulation, but can be ordered with Automatic Level Control (ALC) to maintain linear operation for modulation formats such as QPSK having a variable envelope carrier.

  • 17 Watts typical output power
  • 7.8 - 8.8 GHz frequency range
  • Built-in DC-DC converter and regulator
  • 22 to 36 VDC input voltage
  • High efficiency (28%)
  • GaAs MMIC technology
  • Small size and mass
  • S-level parts
  • Covers deep-space and near earth frequency bands
  • Fully space qualified and radiation tolerant
  • EMC performance qualified to MIL-STD-461C

Specifications

 

X-Band Solid State Power Amplifier

Data Sheet

 

 

View Document

 

RF Output Power: > 15 Watts (17 Watts typical)
Output Power Variation: ±0.25 dB over any 50 MHz band
Input Power: +1 dBm ±2 dB
Input/Output Impedance: 50 ohms
Input/Output VSWR: 1.5:1 maximum
Source/Load VSWR: 1.75:1 maximum
Output Protection: No damage, any VSWR, any phase
Spurious Outputs: < 60 dBc
Harmonic Outputs: < 30 dBc
RF Breakdown Margin: > 6 dB @ VSWR of < 10:1, any phase
User Interface RF Input: SMA-F
RF Output: SMA-F (optional waveguide flange)
DC Power Input: 21-socket Microminiature D
Telemetry/Direct Access: 25-Pin Microminiature D
Input Power Operating Voltage: 22 to 36 VDC
Over/Under Voltage: 0 to +22, +36 to +50 Vdc, no damage
Power: 65.5 Watts max (60 Watts nominal)
Isolation to Chassis: 1 to 100 megohms
Inrush Current Limiter: Optional (reduces efficiency ≈ 1%)
External Sync: 125 kHz ± 10% (optional)
General Maximum Dimensions: 6.85”L x 5.275”W x 1.85”H, excluding
mounting feet
Mass: 3.02 lbs (1.37 kg)
Protoflight/Qualification Temperature: -40°C to +70°C
Flight Acceptance Temperature: -40°C to +60°C
Vibration: 7.9 Grms (protoflight)
Pyrotechnic Shock: 2000 G
Altitude: Sea level to vacuum
Radiation: to 100 krads (Si)

 

  • Features

    Features

    The X-Band Solid State Power Amplifier (SSPA) is designed for use as a companion unit to General Dynamics’ Small Deep Space Transponder (SDST), or it can be used as a stand-alone power amplifier. As shown in the figure in the datasheet, the SSPA is designed to supply telemetry signals that can be connected directly to the SDST to make a complete transmitter/ receiver with a single MIL-STD-1553B data interface. The SSPA also provides a full complement of analog telemetry signals, as well as direct access to selected functions for monitoring during subsystem and spacecraft ground testing. The SSPA operates in compression to maximize efficiency for constant envelope modulation, but can be ordered with Automatic Level Control (ALC) to maintain linear operation for modulation formats such as QPSK having a variable envelope carrier.

    • 17 Watts typical output power
    • 7.8 - 8.8 GHz frequency range
    • Built-in DC-DC converter and regulator
    • 22 to 36 VDC input voltage
    • High efficiency (28%)
    • GaAs MMIC technology
    • Small size and mass
    • S-level parts
    • Covers deep-space and near earth frequency bands
    • Fully space qualified and radiation tolerant
    • EMC performance qualified to MIL-STD-461C
  • Specifications

    Specifications

     

    X-Band Solid State Power Amplifier

    Data Sheet

     

     

    View Document

     

    RF Output Power: > 15 Watts (17 Watts typical)
    Output Power Variation: ±0.25 dB over any 50 MHz band
    Input Power: +1 dBm ±2 dB
    Input/Output Impedance: 50 ohms
    Input/Output VSWR: 1.5:1 maximum
    Source/Load VSWR: 1.75:1 maximum
    Output Protection: No damage, any VSWR, any phase
    Spurious Outputs: < 60 dBc
    Harmonic Outputs: < 30 dBc
    RF Breakdown Margin: > 6 dB @ VSWR of < 10:1, any phase
    User Interface RF Input: SMA-F
    RF Output: SMA-F (optional waveguide flange)
    DC Power Input: 21-socket Microminiature D
    Telemetry/Direct Access: 25-Pin Microminiature D
    Input Power Operating Voltage: 22 to 36 VDC
    Over/Under Voltage: 0 to +22, +36 to +50 Vdc, no damage
    Power: 65.5 Watts max (60 Watts nominal)
    Isolation to Chassis: 1 to 100 megohms
    Inrush Current Limiter: Optional (reduces efficiency ≈ 1%)
    External Sync: 125 kHz ± 10% (optional)
    General Maximum Dimensions: 6.85”L x 5.275”W x 1.85”H, excluding
    mounting feet
    Mass: 3.02 lbs (1.37 kg)
    Protoflight/Qualification Temperature: -40°C to +70°C
    Flight Acceptance Temperature: -40°C to +60°C
    Vibration: 7.9 Grms (protoflight)
    Pyrotechnic Shock: 2000 G
    Altitude: Sea level to vacuum
    Radiation: to 100 krads (Si)

     

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