A method of transmission of data at a terminal of a broadband radio communication system, the terminal being arranged to inhibit the transmission of data dependent on detection of radar pulses, the radar pulses being transmitted with one or more pulse repetition intervals selected from a set of allowed pulse repetition intervals, the method comprising: conducting transmission of data in a frequency channel; receiving a signal waveform at the terminal; detecting a plurality of potential radar pulses in the received signal waveform; ascertaining a reception time for each of the plurality of potential radar pulses; selecting a pair of pulses from the plurality of potential radar pulses, the pair of pulses having respective reception times separated by a selected pulse repetition interval selected from the set of allowed pulse repetition intervals; selecting one or more further pulses, of the plurality of potential radar pulses, related to said selected pair by having a respective reception time separated from the respective reception time of at least one pulse of said pair of pulses by one or more pulse repetition intervals from the set of pulse repetition intervals; discounting at least two other pulses from the plurality of potential radar pulses, the at least two other pulses having respective reception times separated by a pulse repetition interval in the set of allowed pulse repetition intervals, the at least two other pulses being discounted on the basis of not being related to said selected pair by having a respective reception time separated from the respective reception time of at least one pulse of said pair of pulses by one or more pulse repetition intervals from the set of pulse repetition intervals; and inhibiting the transmission of data in said frequency channel at least in part in dependence on the selection of the further pulses related to said selected pair. conducting transmission of data in a frequency channel; receiving a signal waveform at the terminal; detecting a plurality of potential radar pulses in the received signal waveform; ascertaining a reception time for each of the plurality of potential radar pulses; selecting a pair of pulses from the plurality of potential radar pulses, the pair of pulses having respective reception times separated by a selected pulse repetition interval selected from the set of allowed pulse repetition intervals; selecting one or more further pulses, of the plurality of potential radar pulses, related to said selected pair by having a respective reception time separated from the respective reception time of at least one pulse of said pair of pulses by one or more pulse repetition intervals from the set of pulse repetition intervals; discounting at least two other pulses from the plurality of potential radar pulses, the at least two other pulses having respective reception times separated by a pulse repetition interval in the set of allowed pulse repetition intervals, the at least two other pulses being discounted on the basis of not being related to said selected pair by having a respective reception time separated from the respective reception time of at least one pulse of said pair of pulses by one or more pulse repetition intervals from the set of pulse repetition intervals; and inhibiting the transmission of data in said frequency channel at least in part in dependence on the selection of the further pulses related to said selected pair.