Filtering a signal with the use of approximate arithmetical division

DETAILED DESCRIPTION One object of the present invention is to provide a method which will enable an arithmetical division of the kind mentioned in the background to be carried out rapidly and with the aid of simple equipment.
This is achieved in two stages.
There is first formed a digital word, by substituting with logic zeroes any logic ones which have a lower significance than the most significant logic one of the bits which give the absolute value of the variable number.
There is then formed in binary form a new number which has similar character bits to the variable number, and the bits in the digital word are read in the reverse sequence.
Although the division achieved when practicing the method is not exact, it is, however, sufficiently exact for calculating the convergence factor when updating adaptive filters.
For instance, it will be obvious that a high signal energy will give rise to a low convergence factor, and vice versa.
Another object of the invention is to provide an arrangement of the aforesaid kind of simple construction which will enable an approximate division to be carried out rapidly.
The device comprises essentially only one logic device which functions to substitute with logic zeroes any logic ones that have a lower significance than the most significant logic one.