Microwave Coaxial Cable Assemblies

LOROM Excels in High Speed Dielectric Technologies

Dielectric science has enjoyed a long and illustrious history. In addition, this longstanding branch of physics has had close links to chemistry and electrical engineering. Over 130 years ago, Faraday coined the term ‘dielectric’ to suggest that something analogous to current flow occurs through a capacitor structure during the charging process when current introduced at one plate ‘flows’ through the insulator to charge the other plate. It is generally accepted that a dielectric material interacts with an electric field differently than it does with free space because the dielectric contains charges that can be displaced. Since nearly all materials contain charges, essentially every material can be broadly classified as a dielectric.

The quest for the industry has over the last 40 years been approximating the ultimate goal of 100% velocity of propagation, by introducing air into mechanical structures supporting the copper center conductor.

LOROM has been committed to excelling and always being at the forefront of technology curve in offering the latest technology of dielectrics in use in differential as well as single ended transmission structures.

We take pride in being on the forefront offering solutions to the industry challenging signal integrity system requirements.

From the early days of the “bamboo” style of cabling to the latest physical gas injection extrusion technologies and now as of late the revolutionary ePTFE tape wrap and process technology.

LOROM ePTFE tape display the lowest dielectric constant of any high speed dielectric material. By our unique process we expand solid PTFE resin into ePTFE precision tapes, increasing the air volume up to 70% air. Lowering the overall dielectric constant from 2.1 for PTFE to 1.3. Our ePTFE dielectric tape has a tightly and precisely controlled thickness, density and dialectic constant. Choosing our ePTFE tapes as dielectric materials by applying the tape wrapping individual conductors enables lower interference, noise, cross-talk and signal attenuation. As well as creating more phase stable limiting phase shift to 4.3° and signal attenuation to 0.05dB at 110 GHz. ePTFE tape wrapped dielectric and insulation systems can be up to 50% thinner than other materials, increasing I/O packaging.

The Process

Heating the polymer to about 300°C, below its 327°C melting point and then rapidly applying controlled force in one axis, expands the polymer’s microstructure to create air voids due to fillabration in the PTFE.

The expanded polymer appears under atomic force microscopy as a network of densely coiled nodes connected by fibrils.

Controlling the expansion temperature, force, rate and direction allow us to dictate many microstructural attributes of ePTFE, including the network’s openness, density of the fibrils and distance between nodes. Each microstructural configuration, combined with the final product performance, provides us the ePTFE products unique characteristics.

Every good signal integrity high speed transmission line whether its single ended or differential is limited in the ability to maintain tight light control of the Ke (dielectric constant) in:

• Homogenous cell size in the dielectric.
• Even dispersion of cells throughout the entire length of the cable.

40 GHz Microwave Coaxial Cables

Our range of high frequency cable assemblies display ultra low loss for numerous applications such as antennas and applications with need for high power as well as our MCX miniature cable series for applications within for test systems and complex medical applications. Our products are extremely phase stable cables benefitting test & measurement applications.

Our decades of signal integrity engineering experience and detailed knowledge in manufacturing of not only bulk cable but also in cable assemblies results in the highest possible quality products made anywhere in the world.

Our ePTFE microwave cable assemblies are characterized by world-class high frequency performance with unmatched mechanical performances:

• Impedance tolerance of +/- 1 Ohm
• High Phase stability
• Power handling of up to 400W @ 10GHz
• Crush resistance of up to 30N
• Cable assemblies swept to 40GHz
• Guarantee free of insertion loss “suck-outs”
• More than 500 mating cycles (dependent on connector type)
• Up to 30% lower insertion loss (compared to conventional designs)
• Up to 15% smaller diameter (compared to conventional designs)

The low loss 142 series of bulk cable comprise a silver plated inner and outer braid strands to achieve excellent attenuation performance. Our unique state of the art low loss ultra low density expanded PTFE dielectrics are engineered to provide stable electrical performance over temperature extremes and imperative performance as far as Low loss, phase stability. Our optimized shielding technologies result in shielding effectiveness of >100 dB by combining different cable shielding technologies.

20GHz Single Shielded Parallel Pair Cables:

• Impedance tolerance of +/- 2 Ohm
• Swept to 20GHz
• Guaranteed free of insertion loss “suck-outs”
• 5% Difference in Amplitude Skew
• Up to 30% Lower insertion loss
• Up to 15% smaller diameter