There are disclosed techniques (e.g., apparatus, methods) for estimating an Impulse response (30) of a linear System (4). An apparatus (100) is configured to generate (7) a transmit Signal (23) on the basis of a first sequence. The apparatus (100) is configured to obtain a receive Signal (24) and to multiply (9) the receive Signal (24) with a second sequence (25), to obtain a modified receive Signal (26), wherein the second sequence (25) is different from the first sequence. The apparatus (100) is configured to analog-to-digital, ADC, convert (11) an Integration result (27) in order to obtain a sample value (28), the Integration result (27) being based on an Integration (10) of the modified receive Signal (26) over a period (Ts) of time. The apparatus (100) is configured to obtain an estimate (30) of the Impulse response on the basis of a plurality (29) of sample values (28).