Comparative analysis of signal attenuation in coaxial vs twisted pair cables for IoT sensor networks

What determines the reliability of an Internet of Things sensor network in demanding industrial environments? This research addresses the fundamental question of transmission medium selection by presenting a comparative investigation of signal attenuation characteristics between coaxial and twisted pair cables across diverse frequency ranges pertinent to modern IoT applications. The experimental framework involved systematic measurement of attenuation parameters using RG-58 coaxial cables and Category 6 twisted pair cables over distances ranging from 25 to 150 meters. Testing was conducted at the Lyon Institute of Technology telecommunications laboratory from March through September 2024, employing calibrated signal generators and spectrum analyzers operating across frequencies from 10 MHz to 1 GHz. Results demonstrated that coaxial cables exhibited markedly lower attenuation coefficients, particularly at higher frequencies where twisted pair degradation became pronounced. At 500 MHz, coaxial cables showed attenuation of 21.6 dB per 100 meters compared to 45.8 dB for twisted pair configurations. However, twisted pair cables demonstrated acceptable performance for shorter transmission distances below 50 meters when operating under 100 MHz. The findings indicate that deployment environment significantly influences optimal cable selection, with coaxial configurations proving superior for industrial settings characterized by electromagnetic interference. This research provides practical guidance for IoT network designers balancing performance requirements against installation costs and flexibility constraints.