Application of the SZ Phase Code to Mitigate Range–Velocity Ambiguities in Weather Radars
نویسندگان
چکیده
It has been demonstrated through simulations that the SZ phase code method of mitigating range ambiguities has a performance that exceeds any other known phase-coding scheme. This paper describes an implementation of this code on a weather radar and compares its performance with that derived from simulations. Spectral data obtained from NCAR’s S-Pol radar, which had its transmitted phases coded with the SZ(8/64) switching code, are presented to illustrate the steps in this method. It is shown that fully coherent transmitters, such as that used in the U.S.’s WSR-88D weather radars of the National Weather Service, have a system phase stability that takes full advantage of the unique properties of the SZ-coding method. The performance of this coding technique is evaluated by implementing it on a research WSR-88D weather radar. Results verify the dramatic increase in the area of reliable velocities compared to that provided by techniques presently employed in the operations. The performance of the SZ algorithm to retrieve weak signals overlaid by stronger signals is evaluated in the spectral domain by comparing a subjective analysis of the data field where the two overlaid echo spectra can be visually separated and mean Doppler velocities calculated.
منابع مشابه
P5.10 Generalized Sz Phase Codes to Mitigate Range and Velocity Ambiguities
It is well known that for Doppler radars transmitting uniformly spaced pulses there is a coupling between the maximum unambiguous range and velocity. That is, one can only be increased at the expense of a proportional decrease of the other. Because this fundamental limitation hinders observation of severe weather phenomena, the Radar Operations Center of the US National Weather Service has unde...
متن کاملRange and Velocity Ambiguity Mitigation on the Wsr - 88 D : Performance of the Sz - 2 Phase Coding Algorithm
It is well known that for Doppler radars transmitting uniformly spaced pulses there is a coupling between the unambiguous range (ra) and unambiguous velocity (va) given by rava = cλ/8, where c is the speed of light and λ is the radar wavelength. As shown by this relation, ra or va can only be increased at the expense of a proportional decrease of the other. Because range and velocity ambiguity ...
متن کاملWaveform design considerations for CASA radar network
The Center for Collaborative Adaptive Sensing of the Atmosphere (CASA) is embarking on a paradigm of network of small radars to sample the atmosphere at high resolution. A fundamental physical limit imposed by transmission from single radar is the problem of decreasing resolution as a function of range. In addition the lowest coverage altitude increases with range due to earth curvature. As an ...
متن کامل11b.2 Update on Deployment of Staggered Prt for the Nexrad Network
In the NEXRAD network, the range and Doppler velocity ambiguity problems are coupled such that trying to alleviate one worsens the other. Operationally, this is evidenced by the obscuration of overlaid weather echoes and/or the aliasing of measured Doppler velocities, both of which impair the effective observation of weather phenomena. Identified as one of the highest technical needs for the NE...
متن کامل9 . 9 Range and Velocity Ambiguity Mitigation on the Wsr - 88 D : Performance of the Staggered Prt Algorithm
It is well known that for Doppler radars transmitting uniformly spaced pulses there is a coupling between the unambiguous range (ra) and unambiguous velocity (va) given by rava = cλ/8, where c is the speed of light and λ is the radar wavelength. As shown by this relation, ra or va can only be increased at the expense of a proportional decrease of the other. Because range and velocity ambiguity ...
متن کامل