WHISPER relaxation sounder

The Wave of HIgh frequency and Sounder for Probing of Electron density by Relaxation (WHISPER) performs the measurement of the electron density on the four satellites of the CLUSTER project. The two main purposes of the WHISPER experiment are to record the natural waves and to make a diagnostic of the electron density using the radio-wave sounding technique. The various working modes and the Fourier transforms calculated on board provide a good frequency resolution obtained in the bandwidth 2 to 83 kHz. Onboard data compression by the Digital Wave Processing (DWP) intrument allows a good dynamic and level resolution of the electric signal amplitude.All WHISPER datasets are available on the ESA Cluster Science Archive at https://csa.esac.esa.int/

WHISPER（通过弛豫探测电子密度的中高频率声波探测仪）对 CLUSTER 项目中的四颗卫星上的电子密度进行测量。WHISPER 实验的两个主要目的是记录自然波动，并利用无线电波声测技术对电子密度进行诊断。各种工作模式及在卫星上进行的傅里叶变换计算提供了在 2 至 83 kHz 带宽内获得的良好频率分辨率。通过数字声波处理（DWP）仪器在卫星上的数据压缩，实现了对电信号幅度的良好动态和电平分辨率。所有 WHISPER 数据集均可在欧洲空间局（ESA）的 CLUSTER 科学存档中获取，存档地址为 https://csa.esac.esa.int/。