ANORDNIG FOR ALSTRING AV EN FASMODULERAD VAG

摘要

A digital device has an input for receiving successive samples of input data in digital form representative of phase values zeta . A sequence of the most recent input samples is stored in an input memory. A carrier phase source provides a signal representative of the phase theta of a carrier wave. A function memory stores values of a function ki x sin ( zeta n-i+ theta n) and is addressed by first selection means which select a group corresponding to a coefficient ki and second selection means which select a member of the group corresponding to the value of ( zeta + theta ). During a calculation period the sum of all values of the function is calculated for i varying between l and a predetermined number r. Each such sum forms a sample of the output wave which is converted to analogue form and filtered to remove unwanted sampling components.