| 摘要 |
1. Analog operator module which is capable of receiving four voltages a0 , b0 , a1 , b1 and of producing the voltages x1 = (a0 -a1 ) cos 2k pi /N-(b0 -b1 ) sin 2k pi /N y1 = (a0 -a1 ) sin 2k pi /N-(b0 -b1 ) cos 2k pi /N wherein N is an integer and k an integer comprised between 0 and N-1, characterized by the fact that it comprises two operational amplifiers (A01 and A02) with switched capacities mounted identically in the following manner : a looping capacity (C1 ) is connected on one side to the inverting input of the amplifier and on the other side either to ground through a first transistor (T1) or to the output of the amplifier through a second transistor (T2), a third transistor (T3) permitting to short-circuit the output and the input of the amplifier, with a plurality of parallel input capacities each of which is susceptible to be rendered operative or to be insulated by a respective transistor, the values of these capacities, in relation to the value of the looping capacity, being the cosine of angles 2k' pi /N comprised between 0 and pi /4, wherein k' is a transformation of the number k which is such that the angles 2k pi /N and 2k' pi /N are related through simple trigonometric relations comprising sign changes or permutations of sine and cosine, and another pluraity of input capacities mounted in the same manner but having sine values of the same angles, one of the pluralities of capacities receiving on one side the signal a0 through a transistor (Ta ) and the signal a1 through another transistor (T'a ) and being connected on its other side to the input of the amplifier, the other plurality of capacities receiving on one side the signal b0 through a transistor (Tb ) and the signal b1 through another transistor (T'b ) and being likewise connected on the other side to the input of the amplifier, with a symmetry between the mountings of the two amplifiers, i.e. the fact that if the capacities having cosine values receive a0 and a1 for one of the amplifiers, the corresponding capacities of the other amplifier which also have cosine values receive b0 and b1 in reciprocal manner ; the operator module further comprising switching control means (CL) for the different transistors which are capable on the one hand of selecting an input capacity having a cosine value and an input capacity having a sine value of the same angle, this selection being controlled as a function of the number k and on the other hand of establishing synchronised conduction phases between the different transistors in a manner to produce values approaching the quantities x1 and y1 on the outputs of the two amplifiers, the conduction phases comprising at least one phase of applying two of the four voltages a0 , b0 , a1 , b1 to the selected input capacities and a phase of applying the two other voltages to these capacities, the selection of the applied voltages being performed by means of logic circuits (D2) receiving the number k. |
