Wi-Fi in the 2.4 GHz band

The combinations and expected behavior when Wi-Fi® is operating in the 2.4 GHz band in the connected state depend on the transmit (TX) and receive (RX) status of the Wi-Fi and Bluetooth® LE/IEEE 802.15.4 devices.

Depending on the antenna configuration, the Wi-Fi and Bluetooth LE/IEEE 802.15.4 devices can have the following operations:

The following table describes the coexistence behavior for the different RX/TX combinations when Wi-Fi is operated in the 2.4 GHz band in the connected state.

Table 1. Coexistence with Wi-Fi operating in the 2.4 GHz band in connected state
Wi-Fi (2.4 GHz) Bluetooth LE/IEEE 802.15.4 (2.4 GHz) Coexistence behavior
Shared antenna Separate antennas
RX RX Single Concurrent
TX RX Single Single or concurrent1
RX TX Single Single or concurrent1
TX TX Single Single2

1Depending on signal strength some TX/RX related performance effects can occur.

2Concurrent TX/TX is currently not supported.

When both interfaces are operating concurrently (TX/RX or RX/TX), depending on relative signal strengths, there can be some TX/RX related performance effects. For example, receiving short range signals close to the sensitivity limit while Wi-Fi is transmitting results in the 2.4 GHz noise floor being elevated and hence short-range demodulation being degraded.

Concurrent TX/TX is not supported for separate antennas because the coexistence logic assumes that both Bluetooth LE/IEEE 802.15.4 and Wi-Fi signals are overlapping in frequency. This is a worst case scenario as the channel information is not currently shared from the Bluetooth LE/IEEE 802.15.4 interface to the coexistence logic.