Clear Channel Assessment Default Threshold Settings and Impact on Wi-Fi Throughput
Raising default clear channel assessment thresholds boosts aggregate Wi-Fi network throughput in high-density deployments by trading client SINR for spatial reuse.
CCA-CS
Meaning
Clear channel assessment mode utilizing carrier sensing provides a mechanism for a radio to detect whether a frequency is occupied by another transmitter using the same protocol. In this specific implementation, cca-cs triggers a busy status only when the incoming signal matches a known packet structure. This allows the device to ignore generic electrical noise or signals from different wireless standards.
Protocol Specificity
Detection relies on identifying the start-of-frame delimiter or a valid preamble within the incoming radio wave. The protocol specificity of cca-cs prevents a wifi radio from being blocked by a microwave oven or a proprietary sensor network. Baseband logic must decode the first few bits of a transmission to confirm a match.
System Throughput
Efficiency improves when a radio only defers to traffic it can actually decode. The system throughput of cca-cs is higher in noisy environments compared to methods that stop for every energy spike.
Detection Timing
Sensing must happen within a precise window before a scheduled transmission starts. The detection timing of cca-cs is measured in microseconds to comply with physical layer standards. If the hardware takes too long to identify a preamble, it might miss the opportunity to transmit.
Fast logic is essential for high-speed operation.