Antenna Placement Decisions Made Too Late in Enclosure Design
Early co-simulation of enclosure dielectric loading and counterpoise geometry prevents costly mold tooling revisions and regulatory recertification delays.
Time-on-Air Expansion
Meaning
The increase in the duration required for a wireless signal to transmit a packet of data across a radio channel occurs when utilizing lower data rates or higher spreading factors. In low-power wide-area networks, a time-on-air expansion directly affects the throughput and reliability of the wireless link. This parameter must be carefully managed to prevent channel congestion and ensure compliance with regional duty cycle regulations.
Modulation Behavior
Adjusting the spreading factor or decreasing the coding rate in chirp spread spectrum modulation causes the transmitted signal to occupy the channel for a longer duration. This time-on-air expansion improves the receiver sensitivity and extends the operational range of the device. It allows the radio to establish a stable connection with remote gateways even in high-interference environments.
Network Capacity
Long-duration transmissions increase the probability of packet collisions and interference between co-located nodes. If multiple field devices experience a time-on-air expansion simultaneously, the total capacity of the gateway drops significantly. Sourcing and engineering teams must design dynamic data rate algorithms to optimize packet duration based on real-time channel conditions, ensuring that long-duration packets are only utilized when absolutely necessary.
Energy Consumption
Extending the duration of the radio transmission results in a longer active state for the power amplifier. This prolonged active state increases the energy drain on the device’s battery, reducing its field life.