|Acquisition Program: || Objective: ||Design, build and evaluate a low cost, light-weight device that is capable of generating a specified waveform in the time domain given the desired waveform characteristics in the frequency domain such that they can be programmed into the device. The resulting time domain waveform must exhibit all frequency domain characteristics specified. The device should be suitable for use in Real Time Simulator (RTS) systems that cover frequency bands from UHF to W-band.
|| Description: ||Hardware in the Loop (HWIL) systems use a substantial number of waveform generators for evaluating and assessing the performance of a significant number of sensors that utilize a variety of waveforms over a number of RF bands. Current devices are costly and introduce errors, such as quantization errors, offset errors, linearity errors, scale factor errors, and non-monotonic behavior. Consequently, there is a need for a device that is at least an order of magnitude less costly than current devices such as Direct Digital Synthesizers and Digital RF Memories and that can eliminate or reduce the effect of errors.
Future Combat Systems, with a variety of sensors and communication systems, are difficult to simulate because of the huge number of waveform generators needed to execute meaningful Hardware in the Loop (HWIL) simulations because of the cost and diversity of waveforms needed. Other systems, such as Common Missile, that employ more than one sensor, need to be simulated to evaluate their performance potential as well as to predict performance. Again, cost and diversity of waveforms affect the capability to execute creditable simulations. Diversity of waveforms is, of itself, not a limiting factor. Rather, it is the cost associated with the generation of numerous waveforms that is a driver.
The mathematics from which current waveform generation schemes are devised are well established. However, to avoid the errors associated with digitization, the mathematics to formally establish a new design approach may need to be modified/adapted for a new design approach or the mathematics may need to be extended to introduce new waveform generation concepts.
|| ||PHASE I: Develop a preliminary design for the device and evaluate the feasibility for use in RTS systems. Feasibility may be demonstrated using a Linear Frequency Modulated (LFM) waveform as a baseline waveform. Analysis should show how the design can be extended to other waveforms. Analysis may include a digital simulation of the design such that a LFM waveform for example may be generated at the output of the device given a specified set of characteristics for the waveform in the frequency domain. The results of the analysis should be sufficient to fully evaluate and analyze the device’s performance and its capabilities for extension to other waveforms. Any limitations and/or constraints that affect the performance of the device or its extension to other waveforms should be identified and explained. A major goal is to show that the cost of the device does not exceed $20,000 with a cost goal of $10,000. In addition, military and commercial applications of the device will be assessed and a detailed plan for militarization and commercialization will be prepared.
|| ||PHASE II: If the respondent is successful in demonstrating that the requirements of Phase I have been achieved, the respondent will design and build a prototype device operating within an RF band to be specified during Phase I and being capable of generating a minimum of three different waveforms with specified characteristics in the frequency domain. The respondent will demonstrate the performance of the prototype device and analyze the performance results in an environment or system to be specified during Phase I.
|| ||PHASE III: If the prototype is successfully built and demonstrated, there would be significant interest in the military for adapting the technology to numerous systems such as missile systems, air defense systems, ECM/ECCM systems, synthetic aperture radar (SAR) systems. Commercially, there would be interest by law enforcement agencies for countering communications used in criminal activities such as drug trafficking.
|| References: ||1) Deley, Gary W., “Waveform Design,” Skolnik’s Radar Handbook, McGraw-Hill Book Company, New York, New York, Chapter 3, pp. 3-1 to 3-47, 1970.
2) Gill, Gurnam S., “Fourier Series Based Waveform Generation and Signal Processing in UWB,” Ultra-wideband Radar Technology, CRC Press, Boca Raton, FL 33431, Chapter 10, pp. 291-302, 1995.
3) Bell, M. R, “Information Theory and Radar Waveform Design,” IEEE Transactions on Information Theory, Volume: 39 Issue: 5, Sept. 1993, pp 1578 –1597.
4) Gill, G. S., “Ultra-wideband Radar Using Fourier Synthesized Waveforms,” IEEE Transactions on Electromagnetic Compatibility, Volume 39, Issue 2, May 1997, pp.124 –131.
|Keywords: ||Sensors, Radar, Waveform Generation, Simulation, Counter-Measures|