In this paper, sections of P3/P4 polyphase codes are concatenated to construct a new class of polyphase code sets. They are defined by closed-form mathematical expressions, from which code sets can be easily generated with properties dependent on the values of the key design parameters. The phases of the resulting codes need not have any degree of uniformity. However, if desired, then at the cost of slightly degraded correlation and Doppler properties, the phase values of the generated code sets can be quantized to have equally spaced phases on the unit circle. The correlation and Doppler properties of several design examples of polyphase code sets are examined in terms of the autocorrelation, cross-correlation, and ambiguity functions. For comparison with existing quadphase code sets, an example of the proposed code sets is quantized to quadphase. The correlation properties of the resulting quadphase code set are found to be similar but slightly inferior to those of the existing code sets, while they are found to be superior in terms of Doppler tolerance and detection capability. In contradistinction to the proposed sets with both Doppler tolerance and detection capability, the existing code sets are, at best, moderately Doppler tolerant, while they are entirely lacking Doppler detection capability. The receiver is modeled as a matched filter that is decomposed into two parallel parts, the outputs of which allow for the detection of the target's radial direction in addition to its radial speed. For additional improvement in the Doppler properties at the cost of a slight signal-to-noise ratio (SNR) loss and small degradation in the correlation properties, the two parts of the decomposed matched filter can be extended in either direction. Manuscript

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Dr. Qazi has published several articles in the area of fiber doped amplifiers, wireless security, MEMS and photovoltaic energy. He has co-authored two books in the area of "Nanonotechnology for Telecommunications" published by CRC Press and a handbook of research on "Solar Energy Systems and Technologies" published by IGI Global. He also authored two chapters for these books. He is a member of ASEE and a senior life member of IEEE.

Objective The purpose of this study is to evaluate the accuracy of a noninvasive radiofrequency-based device, the Cardio-Pulmonary Stethoscope (CPS), to monitor heart and respiration rates and detect changes in lung water content in human experiments and clinical trials. Methods Three human populations (healthy subjects (n=4), heart failure (n=12) and hemodialysis (n=13) patients) were enrolled in this study. The study was conducted at the University of Hawaii and The Queen’s Medical Center in Honolulu, HI. Measurement of heart and respiration rates for all patients were compared with standard FDA - approved monitoring methods. For lung water measurements, CPS data were compared with simultaneous Pulmonary Capillary Wedge Pressure (PCWP) measurements for heart failure patients, and with change in weight of extracted fluid for hemodialysis patients. Results Statistical correlation methods (Pearson, mixed and intraclass) were used to compare the data and examine accuracy of CPS results. Results show that heart and respiration rates of all patients have excellent correlation factors, r ≥ 0.9. Comparisons with fluid removed during hemodialysis treatment showed correlation factor of r = 0.82 to 1, while PCWP measurements of heart failure patients had correlation factor of r = 0.52 to 0.97. Conclusion These results suggest that CPS technology accurately quantifies heart and respiration rates and measure fluid changes in the lungs. Significance The CPS has the potential to accurately monitor lung fluid status noninvasively and continuously in a clinical and outpatient setting. Early and efficient management of lung fluid status is key in managing chronic conditions such heart failure, pulmonary hypertension, and acute respiration distress syndrome.