Satellite hardware often use connectors that are robust, reliable, and suitable for the harsh environment of space. These connectors need to resist radiation, thermal fluctuations, and micro-vacuum conditions, among other factors. Here are some commonly used connector types in satellite systems:
1. MIL-spec Connectors
Usage: Designed for rigorous military and aerospace applications due to their high reliability and ruggedness.
Limitations: They can be relatively heavy and bulky. Also, while robust, they might be over-specified (and thus more expensive) for some applications.
Technical Specifications:
Compliant with specific military standards (e.g., MIL-DTL-38999, MIL-DTL-5015)
Can support multiple contacts ranging from power to high-speed data
Usually made of corrosion-resistant materials
Here's a table that lists some common MIL-spec connectors used in satellite and aerospace applications, along with their usage, data rate, limitations, and advantages:
Connector Type | Usage | Data Rate | Limitations | Advantages | |
MIL-DTL-38999 | High-density power and signal applications. | Varies, up to several Gbps for some modern versions. | Bulky design, can be over-specified for certain applications. | High reliability, resistant to harsh environments, multiple shell sizes and configurations, EMI shielding. |  |
MIL-DTL-5015 | Power and signal in rugged environments. | Up to several hundred Mbps. | Lower pin density compared to 38999. | Robust and reliable, screw coupling mechanism, cost-effective. |  |
MIL-DTL-28840 | Designed for naval shipboard applications but also used in some space applications. | Up to 1 Gbps depending on configuration. | Limited to certain naval/space applications. | Resistant to shock, vibration, and corrosive elements, high-density configurations available. |  |
MIL-DTL-24308 (D-Sub) | Data and control signals. | Up to several hundred Mbps. | Not as rugged as other MIL-spec connectors. | Standardized pin arrangements, widely recognized and used. |  |
MIL-DTL-83513 (Micro-D) | High-density connections in compact applications. | Up to 1 Gbps. | Smaller pins may be more delicate. | Compact design, suitable for space-constrained applications. |  |
It's important to note that the data rates listed above are general figures. The actual data rate can vary depending on the specific configuration, contact layout, and transmission method used. Furthermore, many of these connectors come in different versions (e.g., Series I, II, III for MIL-DTL-38999) that have slightly different specifications and features.
2. Space-grade D-Sub Connectors
Usage: Often utilized for data and power connections in space applications.
Limitations: Limited pin count compared to some other connectors. They also have a less compact form factor compared to modern high-density connectors.
Technical Specifications:
D-shaped metal shield for mechanical protection and shielding
Pin configurations vary, e.g., 9-pin, 15-pin, 25-pin, etc.
Enhanced shielding for space applications
Below is a table detailing space-grade D-Sub connectors used in satellite applications:
Connector Type | Usage | Data Rate | Limitations | Advantages | |
Space-grade D-Sub (Standard Density) | General-purpose data, power, and signal connections. | Up to several hundred Mbps. | Limited pin count, larger footprint compared to high-density versions. | Proven reliability, broad industry acceptance, and availability. | |
Space-grade D-Sub (High Density) | High-density signal and data connections where space is at a premium. | Up to 1 Gbps depending on pin configuration. | More delicate pins due to smaller spacing. | Increased pin count in a similarly sized package to standard D-Sub. | |
Space-grade D-Sub (Dual Port) | Multiple circuitry connections, often used in PCB applications. | Up to several hundred Mbps. | Slightly larger footprint than other D-Subs due to dual ports. | Allows for increased connections with a single connector interface. |  |
Space-grade D-Sub (Filtered) | Applications sensitive to electromagnetic interference (EMI). | Up to several hundred Mbps. | Additional complexity due to integrated filter. | Built-in EMI filtering to reduce signal noise and interference. |  |
Space-grade D-Sub (Combo) | Mixed signal, power, and data connections within a single connector. | Varies based on pin configuration. Power pins reduce data pin count. | Limited overall pin count due to combination of power and data pins. | Flexibility to combine power and data lines in one connector. | |
While this table offers a general overview, it's essential to understand that the exact specifications, including data rate, can vary based on the specific manufacturer, configuration, and usage environment. When selecting a space-grade D-Sub connector for a particular satellite application, it's crucial to review detailed specifications and consult with the manufacturer or a specialist to ensure compatibility and performance in the intended application.
3. Circular Connectors
Usage: Suitable for industrial and aerospace contexts due to their robust design and environmental sealing.
Limitations: Might require specific tools for mating and demating. Some designs might be bulkier than others.
Technical Specifications:
Variability in pin counts and arrangements
Often equipped with threaded couplings for secure connections
4. SMA, SMB, SMC Connectors
Usage: Used for radio frequency connections in various applications including satellites.
Limitations: Frequency range can be limited based on design. Also, repeated connect-disconnect cycles can wear them out.
Technical Specifications:
Coaxial design suitable for RF applications
Frequency range varies but often used for frequencies up to 18 GHz or more
Here's a table detailing SMA, SMB, and SMC RF connectors commonly used in satellite applications:
Connector Type | Usage | Frequency / Data Range | Limitations | Advantages | |
SMA (SubMiniature version A) | RF, microwave, and millimeter-wave circuits in satellite communication systems. | DC to 18 GHz (standard), up to 26.5 GHz (extended performance) | Not suitable for very high power applications; threading can wear over repeated use. | High reliability; Excellent performance in microwave applications; Wide acceptance in the industry. |  |
SMB (SubMiniature version B) | Lower power RF applications, PCB connections, and quick-connect applications. | DC to 4 GHz | Snap-on mechanism can come undone in high-vibration scenarios. | Quick connect/disconnect snap-on mechanism; Compact design. |  |
SMC (SubMiniature version C) | Used in applications where vibration is a concern, like space and military systems. | DC to 10 GHz | Threaded connection can be slower to mate than snap-on varieties like SMB. | Screw-on mechanism ensures secure connection in high-vibration scenarios; Compact. |  |
Please note that while the frequency range gives an indication of the connector's capability, the actual data rate would depend on the modulation and encoding schemes used in the communication system. Always ensure you consult detailed specifications and manufacturers when selecting connectors for specific satellite applications.
5. LEMO Connectors
Usage: Suitable for applications requiring many connect-disconnect cycles due to their push-pull coupling mechanism.
Limitations: Can be more expensive than other connector types.
Technical Specifications:
Push-pull self-latching system
Variability in pin counts
Here's a general overview of LEMO connectors tailored towards potential space applications:
Connector Type | Usage | Data Rate | Limitations | Advantages | |
LEMO B Series | General-purpose applications in aerospace and space requiring a secure connection. | Varies based on pin count and configuration, often up to several Gbps. | Not as miniaturized as some other LEMO series. | Push-pull self-latching system; multiple key options ensuring connector alignment. |  |
LEMO E Series | Designed for specific high-performance applications including space. | Varies, can handle high data rates due to the quality of construction. | More specialized, may be overkill for basic applications. | IP68 water resistance; can handle high frequencies effectively. |  |
LEMO F Series | High-vibration environments like satellite launch platforms. | Varies, designed more for robustness than purely high data rates. | Slightly bulkier due to robust design. | Designed to resist high vibration and shock. |  |
LEMO M Series | Miniaturized applications in satellites and other aerospace systems. | Varies, optimized for small size rather than ultra-high data rates. | Limited pin count due to miniaturized design. | Extremely compact; lightweight; designed for space-constrained applications. |  |
This table provides a broad overview. It's essential to note that LEMO offers a vast range of connectors across these series, each with its specifications, advantages, and potential limitations. The actual data rate, durability, and other performance metrics can vary based on specific model and configuration. When selecting a LEMO connector for satellite or any high-reliability application, thorough consultation with the manufacturer's datasheets or representatives is vital.
6. Fiber Optic Connectors
Usage: Used for high-speed data transmission in modern satellites.
Limitations: Fragile compared to metal connectors and require careful handling and cleaning.
Technical Specifications:
Support for single-mode and multi-mode fibers
Low signal loss and high bandwidth capabilities
Here's a tabulation of some of the commonly used fiber optic connectors in satellite applications:
Connector Type | Usage | Data Rate | Limitations | Advantages | |
FC/PC | General-purpose space communications. | Up to 10 Gbps or higher. | Bulky compared to some newer designs; Screw-on mechanism can be time-consuming. | High reliability; Excellent return loss; Widely recognized and used. |  |
FC/APC | RF-over-fiber, high-performance applications in space. | Up to 40 Gbps or higher. | Angled polish can complicate connection but offers improved performance. | Lower back reflection than FC/PC; Suitable for high-bandwidth applications. | |
ST | Older satellite systems and ground equipment. | Up to 10 Gbps. | Bulkier than other connectors; Less preferred in modern designs. | Simple to use and connect; Good for multimode fibers. | |
LC | Modern satellite systems requiring miniaturization. | Up to 100 Gbps or higher. | Smaller connector, requires precision during handling. | Compact design; High precision; Suitable for dense connections. |  |
MTP/MPO | High-density connections in satellite systems. | Multi-channel, up to 100 Gbps per channel. | Complex, more challenging to clean and maintain. | Multiple fibers (12, 24, or more) in one connector; High-density solution. | |
MT-RJ | Some space applications requiring compactness. | Up to 10 Gbps. | Limited adoption compared to other types. | Compact; Combines transmit and receive into a single connector. | |
Expanded Beam | Harsh space environments; Reduces contamination concerns. | Varies, typically up to 10 Gbps. | More expensive and bulkier than traditional connectors. | Resilient against dirt and debris; Suitable for space's harsh conditions. | |
Please note that while these data rates provide a general sense of the connector's capability, the actual achievable data rate would depend on various factors, including the quality of the connection, type of fiber used, and specifics of the communication system. When selecting fiber optic connectors for satellite applications, consulting detailed specifications, and manufacturers is crucial.
7. Hermetic Connectors
Usage: Essential for applications where maintaining specific internal conditions is crucial.
Limitations: Typically more expensive and might have limited customization options.
Technical Specifications:
Airtight design to prevent gas leakage
Suitable for vacuum and specific internal condition applications
Hermetic connectors ensure that there is no gas or moisture leakage across the connector barrier. This is crucial for satellite applications, where the vacuum and temperature extremes of space can lead to unwanted out-gassing or the seeping of contaminants. Here's a tabulated overview of some hermetic connectors used in satellites:
Connector Type | Usage | Data Rate | Limitations | Advantages |
Glass-to-Metal Seal (GTMS) | General-purpose hermetic applications in space systems, often used in feedthroughs and bulkhead connectors. | Varies based on pin configuration, but usually up to a few Gbps for signal connectors. | Can be heavier than other types; Not ideal for extremely high-frequency applications. | Robust and reliable; Offers excellent hermeticity; Widely used and recognized. |
Ceramic-to-Metal Seal | Applications requiring higher temperatures or frequencies, like RF and power connections in satellites. | Varies, can handle RF signals and some high-speed data lines. | Can be more expensive than GTMS; Ceramic is brittle. | Excellent thermal stability; Can handle higher frequencies than GTMS. |
Resin Sealed | Light-duty hermetic applications, where full metal or ceramic seals aren't necessary. | Varies, but generally lower than GTMS or ceramic due to potential outgassing. | Less robust than metal or ceramic seals; Potential for outgassing. | Lighter weight; Less expensive than other hermetic connectors. |
Hermetic D-Sub | Multi-pin applications in satellites, where a variety of signal, power, and grounding connections are needed in a compact space. | Up to a few Gbps, depending on pin configuration and count. | Can be bulky; Limited to the number of pins in the D-sub configuration. | Combines the versatility of D-sub connectors with hermetic sealing. |
Hermetic SMA/SMC | RF applications in satellites where hermetic sealing is necessary. | RF frequencies, up to several GHz depending on design. | Specific to RF applications; Requires precise mating. | Combines the reliability of SMA/SMC with hermetic sealing. |
Hermetic LEMO | High-precision applications in satellites requiring hermetic sealing. | Varies, often up to several Gbps. | Can be more expensive due to the precision of LEMO design combined with hermetic sealing. | High precision and reliability of LEMO connectors with added hermetic sealing. |
These are generalized overviews of the types of hermetic connectors available for satellite applications. It's crucial to refer to specific datasheets or manufacturer's specifications when selecting a hermetic connector for a particular application, as the exact capabilities, advantages, and limitations can vary based on the specific design and materials used.
Summary
Connector Type | Broad Usage | Limitations | Key Technical Specifications |
MIL-spec | Military and aerospace | Heavy, bulky, might be over-specified | Compliant with military standards, corrosion-resistant |
Space-grade D-Sub | Data and power connections | Limited pin count, less compact | D-shaped, varying pin configurations, enhanced shielding |
Circular | Industrial and aerospace | Might require specific tools, potential bulkiness | Variable pin counts, threaded couplings |
SMA, SMB, SMC | Radio frequency connections | Limited frequency range, wear out with repeated use | Coaxial design, up to 18 GHz or more |
LEMO | High connect-disconnect cycles | More expensive | Push-pull self-latching, variable pin counts |
Fiber Optic | High-speed data transmission | Fragility, requires careful handling | Support for single and multi-mode fibers, high bandwidth |
Hermetic | Applications requiring specific internal conditions | More expensive, limited customization | Airtight design suitable for vacuum applications |
This document provides a general overview of satellite connector types. In practice, when selecting connectors for a specific satellite mission, you'd need to delve deeper into each connector's detailed specifications, considering factors like temperature resistance, radiation tolerance, and specific mission requirements.
Cite this article as: Kumar, Yajur. “Various Connectors in Satellite Hardware: A Detailed Overview” Space Navigators, 23 August 2023, https://www.spacenavigators.com/post/various-connectors-in-satellite-hardware-a-detailed-overview