Cable length can absolutely make a big difference in the function of the antenna. Ideally, you want to design in a cable that fits the design without sacrificing cable placement or data loss.
Cables that are too long for the design will not only take up valuable space but result in cable loss, a condition that happens when signal is lost as the power moves through the cable to the termination points. Cable loss is measured in decibels per unit length at a specific frequency and the amount of loss is proportional with cable length.
Cable loss happens for a variety of reasons either due to internal conditions of the cable or from external factors such as the environment:
- Radiated loss comes from poorly constructed cables that aren’t intended for data transmission. Fortunately, radiated loss doesn’t account for a large amount of data loss.
- Dielectric loss is due to heat inside the cable .
- Resistive loss occurs because the conductors and the current cause resistance .
- Loss over time is caused by wear and tear. It could be moisture, weathering, bending, and more.