Bluetooth LE is a very useful standard that uses low power radios to communicate with devices over short distances. It has many attractive features not the least being very low power consumption. Here is a brief list of the features of the Bluetooth LE radios. The modulation used is GMSK ( Gaussian Frequency Shift Keying) and the frequency band is the 2,4 Ghz ISM band.A ‘0’ bit uses a negative frequency deviation while a ‘1’ bit uses a positive frequency deviation. 40 channels can be used. The center frequency of the lowest channel is 2402 Mhz while the center frequency of the highest channel is 2480 Mhz. To calculate the center frequencies of the channels use: fcenter(i) = 2402 + 2i  Mhz. i varies from 0 to 39.The center frequency tolerance is + or – 150Khz. The center frequency cannot drift by more than 50 Khz during a packet transmission. The transmit power is a maximum of +10 dBm and the minimum is -20dBm.The receiver sensitivity is – 70 dBm The sensitivity threshold is set at 0,1% BER. Some numbers for operating range can be calculated using a LINK BUDGET with a theoretical isotropic antenna and by ignoring any transmit or receive losses. For the minimum transmit power the range is approximately 2.5 meters. For the maximum transmit power the approximate range is 80 meters. Of course this depends on the receiver sensitivity. These numbers are for the minimum receiver sensitivity of -70 dBm.