| CPC H04W 74/0808 (2013.01) | 11 Claims |

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1. A channel sensing device, implemented in a wireless receiver in a wireless system, for detecting a presence of a preamble transmitted by a wireless transmitter over a wireless transmission channel in said wireless system, the channel sensing device being configured to detect the presence of the preamble by observing a channel sensing sequence of a given length smaller than or equal to a maximum given length, said channel sensing sequence comprising one or more samples, wherein the channel sensing device:
receives input parameters comprising a target reliability metric, a receiver noise profile, said maximum given length, a received power, and a probability of a presence of a preamble;
determines channel sensing parameters given said input parameters and according to the minimization of the average energy consumption per given length, said channel sensing parameters comprising a number of channel sensing phases, and a number of samples, a receiver power consumption value, and a preamble detection threshold corresponding to each of said channel sensing phases;
performs a first channel sensing phase comprising:
observing a batch of samples of said one or more samples by consuming the receiver power consumption value corresponding to the first channel sensing phase, said batch of samples comprising a number of samples equal to the number of samples corresponding to the first channel sensing phase;
applying a hypothesis test comprising the comparison of a value derived from the observed samples with the preamble detection threshold corresponding to the first channel sensing phase;
deciding on the presence of a preamble or on performing a subsequent channel sensing phase depending on said comparison and/or whether the number of channel sensing phases is greater than one; and
a subsequent channel sensing phase comprising:
observing a batch of samples of said one or more samples by consuming the receiver power consumption value corresponding to said channel sensing phase, said batch of samples comprising a number of samples equal to the number of samples corresponding to said channel sensing phase;
applying a hypothesis test comprising the comparison of a value derived from all of the so far observed samples with the preamble detection threshold corresponding to said channel sensing phase;
deciding on the presence of a preamble or on performing a subsequent channel sensing phase based on said comparison and/or on a condition related to a number of performed channel sensing phases compared with said number of channel sensing phases.
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