Method and apparatus for generating a frequency estimation signal

A frequency estimation signal generator component arranged to receive an input frequency signal and to generate therefrom a frequency estimation signal, the frequency estimation signal generator component comprising:

• a counter component arranged to receive an oscillating signal derived by dividing the input frequency signal with a divider component and to output a plurality of physically separate digital control signals, wherein the counter component is arranged to output a temporal sequence of control signal patterns for each of the physically separate digital control signals and is controllable by the received oscillating signal to sequentially step through the control signal patterns;
• and
• a continuous waveform generator component arranged to receive the plurality of physically separate digital control signals output by the counter component and a weighted analogue signal for each of the received physically separate digital control signals, and to output a continuous waveform sinusoidal signal comprising a sum of the weighted analogue signals for which the corresponding physically separate digital control signals comprise an asserted logical state;
• wherein the frequency conversion component is arranged to derive the frequency estimation signal from the continuous waveform sinusoidal signal output by the continuous waveform generator component.