wifi module with NRF24L01, frequency: 2.4 GHz band, the maximum transmission speed of up to 2 Mbps, low-power mode
The nRF24L01+ transceiver module is designed to operate in 2.4 GHz worldwide ISM frequency band and uses GFSK modulation for data transmission.
The data transfer rate can be one of 250kbps, 1Mbps and 2Mbps.
Logic Inputs 5V Tolerant
Communication Range800+ m (line of sight)
The nRF24L01+ transceiver module communicates over a 4-pin Serial Peripheral Interface (SPI) with a maximum data rate of 10Mbps. All the parameters such as frequency channel (125 selectable channels), output power (0 dBm, -6 dBm, -12 dBm or -18 dBm), and data rate (250kbps, 1Mbps, or 2Mbps) can be configured through SPI interface.
The SPI bus uses a concept of a Master and Slave, in most common applications our Arduino is the Master and the nRF24L01+ transceiver module is the Slave. Unlike the I2C bus the number of slaves on the SPI bus is limited, on the Arduino Uno you can use a maximum of two SPI slaves i.e. two nRF24L01+ transceiver modules.