| 摘要 |
<p>A digitally Controlled oscillator is provided with a memory, storing the half periods Ti (i = 1, 2, ..., n) of corresponding frequencies fi=? to be generated, and with a digital feedback circuit, in which circuit the half periods taken from memory are decreased by a fixed time value ? on a time sharing basis, and in which circuit, as soon as the obtained residual values .DELTA.i,1=Ti-ki,1?<?, these residual values are increased by the corresponding half periods Ti also on a time sharing basis, and each value so increased is repeatedly decreased by the fixed time ?. On repeating this process j times, the residual values can be expressed by: .DELTA.i,j=Ti + .DELTA.i,j-1-ki,j?, where each ki,j is so large that O?.DELTA.i,j<?. The digital feedback circuit is connected to n residual value counters, which are each supplied with a series of residual values .DELTA.i,j and which, on reaching a fixed value, bring about that a circuit connected to the respective counter produces a square-wave signal of frequency fi.</p> |
