A method of performing a radar sensing function in a mobile communication device (101, 501) that operates in a Time Division Duplex, TDD, (115, 515) wireless communication system having an air interface that comprises a plurality of uplink symbol times associated with symbols transmitted in an uplink direction and a plurality of downlink symbol times associated with symbols transmitted in a downlink direction, and in which each transmitted symbol from a plurality of transmitted symbols has a corresponding cyclic prefix (205, 525, 529) that is transmitted immediately before the corresponding transmitted symbol, and that is a repetition of an end part of the corresponding transmitted symbol, the method comprising: using information about a path delay (121, 123, 521, 523) between the mobile communication device (101, 501) and a receiver (103, 105, 107, 503, 505, 507) as one of one or more bases to determine a timing of a radar operation window (215, 615) comprising a radar signal transmission time and a radar backscatter reception period, and transmitting the radar signal (111, 509) at the determined radar signal transmission time; and characterized in that: the radar operation window (215, 615) has a duration that is shorter than a duration of a cyclic reception window (201, 525, 529) of the receiver (103, 105, 107, 503, 505, 507) and the determined timing of the radar operation window (215, 615) is configured to cause the radar signal (111, 509), when transmitted from the mobile communication device (101, 501) at the determined radar signal transmission time, to arrive at the receiver (103, 105, 107, 503, 505, 507) during a portion of the cyclic prefix reception window (201, 525, 529) of the receiver (103, 105, 107, 503, 505, 507). using information about a path delay (121, 123, 521, 523) between the mobile communication device (101, 501) and a receiver (103, 105, 107, 503, 505, 507) as one of one or more bases to determine a timing of a radar operation window (215, 615) comprising a radar signal transmission time and a radar backscatter reception period, and transmitting the radar signal (111, 509) at the determined radar signal transmission time; and characterized in that: the radar operation window (215, 615) has a duration that is shorter than a duration of a cyclic reception window (201, 525, 529) of the receiver (103, 105, 107, 503, 505, 507) and the determined timing of the radar operation window (215, 615) is configured to cause the radar signal (111, 509), when transmitted from the mobile communication device (101, 501) at the determined radar signal transmission time, to arrive at the receiver (103, 105, 107, 503, 505, 507) during a portion of the cyclic prefix reception window (201, 525, 529) of the receiver (103, 105, 107, 503, 505, 507). the radar operation window (215, 615) has a duration that is shorter than a duration of a cyclic reception window (201, 525, 529) of the receiver (103, 105, 107, 503, 505, 507) and the determined timing of the radar operation window (215, 615) is configured to cause the radar signal (111, 509), when transmitted from the mobile communication device (101, 501) at the determined radar signal transmission time, to arrive at the receiver (103, 105, 107, 503, 505, 507) during a portion of the cyclic prefix reception window (201, 525, 529) of the receiver (103, 105, 107, 503, 505, 507).