Sea-detecting Radar Data Issue 1, 2022

The data in this issue is the radar experiment data under the condition of sea state changed from level 5 to Level 2. During the experiment , the sea state is a process from low to high and then from high to low. At the beginning, the wave height is 1.8m medium wave, level 4 sea state, and at the end, the wave height is 0.4m light wave, level 2 sea state, including wind speed up to 16.7m/s, wave height up to 2.8m high, level 5 sea state. The SPPR50P-HH and SPPR50P-VV were two independent solid-state power amplifier surveillance/navigation radars with identical configurations except that the waveguide slit antenna was horizontally polarized (1.8 m long) and vertically polarized (2.4 m long), respectively. The two radars work in the X-band, adopt the solid-state power amplifier combined pulse transmission system, the use of pulse compression technology, the transmission time is 40ns~100us, the peak transmitting power is 100W, the highest range resolution is 6 meters. During the data collection, the radar was set up at the site of Yantai First Bathing Beach. The two radars, SPPR50P-HH and SPPR50P-VV, were set up near each other with a height of about 80 meters. The vertical height of the two antennas was staggered by more than 1 meter, with SPPR50P-HH on top and SPPR50P-VV on bottom. Both are set to work at a range of 6 nautical miles, and the staring angle of the two radars is manually set, so that the two radars stare at the same scene at the same time. The combined pulses emitted are monomulse signal T1, LFM pulse signal T2 and LFM pulse signal T3 in order of time, and the overall pulse repetition frequency of the combined pulse (T1+T2+T3) is 2000Hz. The staring scene during the experiment contained light buoy 1, at 2.97 nautical miles, shape characteristics: red column, pot top mark, construction: steel float, as shown in the picture on the left below; Light buoy 2, 3.19 nautical miles, shape characteristics: green column, conical top mark, construction: steel float, as shown in the right picture below.Special note: The radar data released in this issue is the echo data of two radars collected separately. The original echo data collected included all T1 echo signals and the first half of T2 echo signals. The released data were preprocessed as follows: First, IF digital quadrature demodulation was performed to form zero IF I/Q data without any extraction during demodulation. The sampling frequency was 60MSPS, corresponding to a sampling interval of 2.5m; In the second step, The T2 pulse echo data is processed by matching filtering and pulse compression, and Hamming window is added. In the third step, 950 points are intercepted from T1 pulse echo data, 1000 points are intercepted from T2 pulse echo data, and a total of 131072 pulses are stored to form amplitude_complex_T1 and amplitude_complex_T2 complex data variables. The header protocol is consistent with the previously published header protocol. For detailed data, please see the attachments: 20221112-1115_SPPR50P_HH_continuous acquisition experimental data report of clutter and floating targets under high and low sea states. pdf, 20221112-1115_SPPR50P_VV_continuous acquisition experimental data report of clutter and floating targets under high and low sea states. pdf . The current data references are as follows: [1] GUAN Jian, LIU Ningbo, WANG Guoqing, et al. Sea-detecting radar experiment and target feature data acquisition for dual polarization multistate scattering dataset of marine targets[J]. Journal of Radars, 2023, 12(2): 456–469. doi:10.12000/JR23029 [2] LIU Ningbo, DING Hao, HUANG Yong, et al. Annual Progress of Sea-detecting X-band Radar and Data Acquisition Program[J]. Journal of Radars, 2021, 10(1), doi: 10.12000/JR21011 [3] LIU Ningbo, DONG Yunlong, WANG Guoqing, et al. Sea-detecting X-band radar and data acquisition program[J]. Journal of Radars, 2019, 8(5): 656–667. doi:10.12000/JR19089