Abstract: A method includes determining a sequence of first coefficient estimates of a communication channel based on a sequence of pilots arranged according to a known pilot pattern and based on a receive signal, wherein the receive signal is based on the sequence of pilots transmitted over the communication channel. The method further includes determining a sequence of second coefficient estimates of the communication channel based on a decomposition of the first coefficient estimates in a dictionary matrix and a sparse vector of the second coefficient estimates, the dictionary matrix including filter characteristics of at least one known transceiver filter arranged in the communication channel.

Abstract: In a method for channel estimation of an OFDM signal transmitted via a channel, an initial channel transfer function is calculated by channel estimation. A channel impulse response is calculated on the basis of the initial channel transfer function. Values of the channel impulse response or of a filtered channel impulse response are classified as noise or as a signal as a function of the level of the values of the channel impulse or of the level of the values of the filtered channel impulse response. A noise-reduced channel impulse response is calculated on the basis of the channel impulse response using the classification, and a noise-reduced channel transfer function is calculated on the basis of this noise-reduced channel impulse response.

Abstract: In an embodiment, a radio device is provided. The radio device may include a signal transmitter configured to transmit a plurality of signals, the signals being transmitted with different intensities; a response receiver configured to receive a response message to one of the transmitted signals from a radio communication device having received the respective transmitted signal of the plurality of transmitted signals, the response message identifying the received message; and a assessment circuit configured to assess the reachability of the radio communication device from the radio device based on the intensity of the signal to which the radio communication device has responded.

Abstract: In a method for channel estimation of an OFDM signal transmitted via a channel, an initial channel transfer function is calculated by channel estimation. A channel impulse response is calculated on the basis of the initial channel transfer function. Values of the channel impulse response or of a filtered channel impulse response are classified as noise or as a signal as a function of the level of the values of the channel impulse or of the level of the values of the filtered channel impulse response. A noise-reduced channel impulse response is calculated on the basis of the channel impulse response using the classification, and a noise-reduced channel transfer function is calculated on the basis of this noise-reduced channel impulse response.