Electronic devices are getting more advanced daily, and their size and weight are also dwindling, making them portable and usable for consumers.
Further, all these devices are high-power and high frequency, requiring high signal transmission speed.
For that, industries use micro-coaxial cables. This article will discuss details about micro-coaxial cable assemblies.
What are micro-coax cables?
Micro coaxial cables, also known as mini coax, are lightweight mini antenna cables with 50-ohm impedance.
Due to their low capacitance and signal loss characteristics, you can use them in high-frequency applications, especially ones with hinges and articulating components.
These cables are named so as they have small outer diameters, useful in applications with limited space.
The structure of micro-coaxial cables is very much similar to standard coax cables with a stranded central conductor covered with single or double shielding.
The classification of micro coax cables depends on their outer diameters in mm. They are:
- 1.13mm-1.32mm
- 1.37mm
What are micro coax connectors?
Micro coaxial connectors (MCX) are snap-on connectors that connect micro coaxial cables.
Their structure is quite similar to SMB connectors but nearly a third smaller.
Other than these, there are MMCX or miniature micro coax connectors that mate with a lock-snap mechanism and can rotate at their connection.
MMCX connectors can support frequencies up to 6 GHz and have 50-ohm impedance.
You can use them with internalized antennas or simplify the connection between an external antenna and a device.
Coax cable connectors
Industries needing mini coax assemblies
More and more applications need high-density RF interconnection solutions, especially in the following;
Avionics:
As you know that all avionics have minimal space to accommodate various application needs in the given airframe.
Engineers may need up to 100 antennas on the aircraft for advanced avionics applications.
As the antenna number increases in aircraft systems, there will be more signal paths; thus, you will need more RF to interconnect solutions to enclose them.
5G services:
As 5G services become more prevalent, companies deploy more antennas to provide full coverage for lower FR1 (below 6 GigaHertz) and higher FR2 frequencies.
Densification of antennas helps deliver ultra-low latency, the highest data speeds, increased network capacity, enhanced reliability, and improved 5G availability.
Several 5G networks also install MIMO antennas, much smaller in size, and these antennas can fulfill larger bandwidth needs.
As a result, now there are a larger number of antennas in lesser space and thus more Radio Frequency interconnections in those small spaces.
The electronic densification in 5G networks is evident because there are various 5G mini cells like micro, femto, and pico.
These cells are placed very close to the wireless microcell towers, sometimes just 100 yards away.
As the demand for portable and small electronic devices grows, the high-density cable assemblies’ requirements to accommodate all connections in compact installations are continuously growing.
Space:
In space, you need lightweight, reliable, compact equipment which can withstand high vibrations, radiation, shock, and a wide range of temperatures.
One advantage of RF coax cable assemblies is that they can work in the smallest footprints.
Further, HF cables must support low-loss communications needing a dense antenna network.
Hard drive:
With the improvement in high-speed internet and large memory devices, you can now enjoy high-quality videos and images on your devices like tablets, smartphones, or personal computers.
The amount of information to be processed dramatically increases, and the signal transmission speed gets faster.
You can use cables and FPC/FFC to transfer signals between module boards of devices in jumper connections.
The cables required in these connections highly depend on the signal transmission and transmission distance.
Micro-coax and Twinax cables are generally considered better for high-speed and long-distance transmission used in jumper connections.
Hard drive parts
Why is micro-coaxial cable preferred over FFC and FPC?
Here are some reasons why micro-coaxial cables offer better performance.
Signal transmission advantages of micro-coaxial cable:
The characteristics related to signal transmission depend on parameters like insertion loss, characteristic impedance, crosstalk, and return loss.
Micro-coax cables have a central conductor, a dielectric layer, and an outer conductor, which are suitable for matching impedance and also get stabilized at a particular impedance.
While matching to some specific impedance, a micro coax cable can secure a larger cross-sectional area at the center conductor than FFC/FPC.
As a result, there is less insertion loss and return loss.
The outer layer of the micro-coaxial cables works as an electromagnetic shield.
As a result, the transmission of the signal through the central conductor is less susceptible to EMW from the outer side.
Additionally, the external shielding effect also reduces crosstalk between different signal lines.
Mechanical advantages of micro-coaxial cables:
Micro-coaxial cables have higher flexibility than shielded FPC/FFC, thus maintaining their electrical characteristics even in bent positions, such flexible micro-coax assemblies are significant requirements in devices with hinges with frequent movements.
They are routed in devices like rotating cameras on drones or in hinges of notebook PCs.
FFC
High-density RF interconnection solutions:
Earlier, high-density Radio frequency interconnections solutions comprise individual assemblies having numerous coax connectors, and now, they have evolved to form one connection port only.
You can find a wide range of high-density connector options to meet the specific connectors of an industry. These options include;
Mini-multi port and Multiport connectors:
In highly dense avionics applications, you have less space, limited accessibility for maintenance, and require critical performance; for such applications, you need Multiport and mini-multiport connectors as they have multiple coax contacts for a similar interface, which are integrated into one connector module/shell.
You have multiple options in these connectors, including ones with reduced weight and size, providing electromagnetic (EM) shielding and offering phase stability with low Voltage standing wave ratio (VSWR).
Further, the multiport connectors have an insertion loss of 20GHz, while mini-multiport connectors have a 40 GHz insertion loss.
Bundled cable solutions:
As densification increases, technicians face significant challenges associated with installations, weather sealing, torquing, and more.
Further, with the advent of complex technologies like 5G, devices are getting smaller and smaller, creating more challenges related to the size and weight of the equipment.
In applications with multiple runs like 5G, bundled cable solutions help create flexible antenna jumpers, creating a spiral form of numerous flexible/ ultra-flexible jumper cables with a common outer polyurethane jacket becomes easy.
The manufacturing of such bundled solutions required the spinning of individual coax cables so that they easily flex, resulting in a bundle that runs through a jacket.
With this design, you can put 4-5 individual coaxial cables to the rear of the MQ4 and MQ5 bundled connectors incorporating multiple Radio Frequency ports.
As a result, the quantity of cables to be hooked reduces. Also, such solutions are pretty rugged, weatherproof, and ultraviolet-resistant.
Further, it saves a lot of labor, as when four to five conductors are in a single bundle, there is no need to do independent l weather seals.
Along with this, the issues of coupling torque also reduce with the reduction of weather seals as the higher the weather seal; the more the chances of developing a mark of water ingression may result in multiple problems, including shutting down the system.
Industries use IP67 to seal male/ female cluster connectors and connector bodies.
Similarly, the transition from connector to bundled cables in a bundled solution is also sealed by IP 67.
Finally, the problem of hooking up faulty/wrong cables and wrong ports also minimizes. There is no requirement for torque wrenches or any special technical know-how.
Locking mini blind mates:
The mini-locking blind mate connectors have overcome the performance issues of the SMP connectors, which are highly susceptible to EMI, water and salt ingress, and EMC interference.
TLMB connectors are rugged and sealed to withstand and work in harsh environments but with better shielding, environmental, and power capacity for a frequency ranging from DC to 60GHz.
Other than EMI and shielding issues, SMP connectors always affect other equipment while performing.
They often result in signal leakage problems as there is a lack of efficient shielding and electric bonding; as a result, the conductor is exposed to external influences.
In such cases, it is required to place the conductors at a larger distance to prevent signal interference.
As TLMB connectors have better shielding, it is possible to accommodate more cables and conductors in a small footprint without signal interference problems.
Another significant problem with SMP connectors is the ingression of salt, liquid fuel, and other impurities.
SMPs have mechanical openings which lack environmental seals. As a result, the tendency of corrosion is high in them.
Further, SMP connectors have an easy connect-disconnect design, becoming a problem in high-vibration systems.
This easily connect-and-disconnect design often leads to undesirable un-mating of the connections in environments like powerful weapon platforms and weapon launches.
On the contrary, TLMB connectors are highly reliable in high-vibration systems like aerospace and military.
Cable assemblies for dense in-the-box systems:
Another requirement in high-density environments is to minimize the footprint behind connectors so that installing multiple cables becomes possible in tiny spaces.
Further, in space and avionics applications, it is also essential to minimize space between connectors and cables so that these interconnect systems survive in high-vibration conditions.
It is possible to bend these cable assemblies around densely packed corners and behind the connectors to reduce footprint, thus saving space and simplifying cable routing.
Originally manufactured for space applications, these high-performance assemblies use compact, flexible, phase stable, and micro coaxial cables, which can be easily packed in-the-box systems.
Micro coax cable assemblies at Cloom:
Cloom offers a wide range of high-performing point-to-point solutions. You can use them on PCBs and other low-profile terminating points to transfer critical signals.
There is no limit to order quantities, and we accept small and large orders for connector types, wire gauges, custom lengths, cable jackets, and EMI/RFI shielding.
Different connector options:
- MHF3
- MHF
- MHF5
- MHF4
- GPPO
- GPO
- G3PO
- G4PO
- Precise RF ( MMCX, SMA, other)
- Fine wire and direct-to-board connections to 0.175mm. The boarding level plug options include MMCX, SSMA, IPEX, Murata, and SSMP.
We also provide different connection configurations like MHFs to SMAs, SMA to MMCXs, G4pos to SMA, and MHFs to MHFs connectors.
Applications:
- medical equipment,
- military applications,
- security devices
- high-end automatic test equipment.
- Display applications such as LCDs, FPDs, PC notebooks, PDAs, cellphones, and digital video cameras.
Characteristics:
- Lightweight and minor diameter for easy routing
- High heat resistance and excellent electrical properties
- High mechanical strength and flexibility
- Pure copper alloy manufacturing
- RoHS-compliant and UL-approved
Molded Mini coax assemblies:
You can get robust connections delivering RF transmission performance with molded mini coax cable assemblies.
The different angle mold types make it possible to route cables according to the requirement.
Also, various accessories like housing insert, backplane frame, and press-in-cable housing make customized connections possible.
Conclusion:
As the applications requiring high-resolution cameras and panels are increasing along with the ones requiring high signal transmission speed, micro-coax cables with mechanical advantages and high-speed signal features are growing in demand.
However, high-density applications require cable assemblies to be easily installed and withstand high vibration and environmental seals.
Contact us for more information regarding our micro coaxial cable assemblies; our professionals can guide you to get the best cable assemblies.