The Design, Based On Dds And Pll Frequency Sweep Signal Source

The basic theories of the frequency synthesis, PLL, DDS, DDS+PLL are introduced at first in this paper. Subsequently, some questions about the design of the system on frequency synthesis are discussed. At last, the scheme of subject, the functional realization of each module, some questions which must be pay much attention in the system design, and the ultimate testing result of this subject are represented and analyzed in detail.The hybrid frequency synthesis technology - DDS+PLL used in the subject have many advantages. Using this method, the merits of DDS such as super fine frequency resolution, high frequency accuracy, easy programmed can be in combination with the excellent character of narrow-band tracing filter merits of PLL. Thereby, the wideband sweep function and specification of the system can be realized.