Wideband Direct Digital Synthesizer

This proposal presents two approaches to increase the DDS analog output bandwidth beyond 2.5GHz to extend the required frequency hopping bandwidth for advanced satellite communications. As the sole supplier of > 3GHz DDS and other DAC-related high-speed mixed signal products in the worldwide open market, the proposed approaches are based on Euvis’ existing 3.2GHz DDS products to minimize risks. The prime approach we propose to improve the analog output bandwidth of the DDS is the parallel-interleaved architecture with Double Sampling Rate (DSR) DAC, where parallel implementation of digital functions allows faster processing with little demand for increased transistor speed while the DSR DAC double the analog output sampling rate and the corresponding output bandwidth. The second approach is to utilize the 2nd and the 3rd Nyquist band with Euvis patented Return-to-Zero or Complementary Interpolation DACs. The module to be proposed includes the developed DDS IC integrated on PCB with FPGA as the pseudo-random code generation, data storage and control functions. Then the data modulated single sideband IF signal will be up-converted to 5GHz or higher. The module will have the operating characteristics of low cost, sub-microsecond hopping time, low spurious content, small size, power and weight. BENEFIT: We have established many customer bases through the selling of our 2 ~ 3 GHz DDS and other 2 ~ 4 GHz DAC-related products in the past 3 years. These customers include both defense companies and commercial industries. The applications covered satellite communication spread spectrum terminals (SCAMP program), Radar, EW, DRFM, Software Defined Radio, scene generation, fast tuning frequency synthesizers, arbitrary waveform generations, UWB, WLAN testing and hard drive testers. We have frequently got requests from these customers about the availability and schedule for the next generation wider bandwidth DDS products. As the frequency band of commercial wireless communication systems are pushing from 900 MHz , 1.9 GHz to 5.8 GHz and even higher, there are big commercial opportunities to use the wideband DDS for frequency hopping wireless data modem applications. The availability of the new DDS product with wide bandwidth will enable many of our existing customers to start designs with this new product to improve their system performance. It also will penetrate into consumer wireless communication markets. The commercialization channel already exist for Euvis and there will have more commercial markets to be explored as the wider bandwidth DDS is available.