How to Select a Coaxial Cable:
Prior to purchasing a coaxial cable, it is essential to understand one of its critical parameters: signal attenuation. When an RF signal traverses the cable, a portion of it is converted into heat, while another part may leak through the outer conductor. Signal loss is typically quantified in decibels (dB) per unit length.
Factors Influencing Attenuation
Attenuation is influenced by several factors, including conductivity, dielectric loss, and environmental conditions:
1. [Cable Size] Larger-diameter cables exhibit lower conduction losses, thereby reducing signal attenuation.
2. [Dielectric Material] Dielectric losses are independent of cable size but increase linearly with frequency.
3. [Conductor Material] Conductor losses rise proportionally with the square root of the frequency.
4. [Temperature] As temperature increases, both the impedance of the conductor and the power factor of the dielectric material increase, leading to higher attenuation.
Conclusion
1. Thinner cables result in greater attenuation.
2. Longer cables also contribute to increased attenuation.
Technical Specification
| Name | Value |
| Cable | RG178 Coax |
| Connector 1 | CRC9 |
| Connector 1 Orientation | Right Angle |
| Connector 1 Polarity | Normal |
| Connector 1 Gender | M |
| Connector 1 Material | Gold |
| Connector 2 | SMA female |
| Connector 2 Gender | M |
| Connector 2 Orientation | Straight |
| Connector 2 Polarity | Normal |
| Connector 2 Material | Gold |
| Length (mm) | 100 |
Low loss SMA female to SMA male cable assembly using Keesun RG178 coaxial cable
The RG178 coaxial cable used in this SMA cable assembly uses PE (F) dielectric with 83% VoP parameter, which has the advantage of low insertion loss compared to solid state dielectric. This flexible RF cable assembly is ideal for applications in environments that require bending.
