Issues of developing receiving equipment for the passive method of induced polarization

Abstract The article deals with the design of receiving equipment for the passive method of induced polarization (IP). It is shown that the best option for recording this kind of signals is a circuit with an input analogue part and amplification of 50-100 times, as well as an input gain of at least 3 MΩ and a digital part based on a modern twenty-four-bit analogue-to-digital converter (ADC). In this case, it is preferable to use one ADC per channel without multiplexing, for better suppression of inter-channel interference. Signal processing is performed using modern microcontrollers based on the Cortex M4 core, and then the data is transmitted via Bluetooth to a laptop or tablet, where visualization and post-processing is carried out. Thus, the proposed scheme for the implementation of the receiving equipment meets all the requirements for the receiving equipment for the passive IP method, and can be introduced into the practice of field work.

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Open source hardware for counting and measuring raindrops

10.5194/egusphere-egu21-2289 ◽

2021 ◽

Author(s):

Nick van de Giesen ◽

Rolf Hut ◽

Dirk van der Lubbe - Sanjuan

Keyword(s):

Signal Processing ◽

Open Source ◽

Operational Amplifier ◽

Digital Converter ◽

The Core ◽

The Past ◽

Piezoelectric Elements ◽

Analogue To Digital ◽

Open Source Hardware

<p>Over the past years, simple acoustic drop detectors have been developed for different objectives. The core of these detectors were standard piezoelectric elements. For some applications, such as simply counting drops, not much signal processing is needed. For other applications, however, such as measurement of drop energy, which would allow for estimation of drop sizes as well, careful signal processing is needed. For this purpose, we have developed a shield, or &#8220;Wing&#8221; that can be plugged into an Adafruit Feather (https://www.adafruit.com/feather), which we call DisdroWing. This board includes a high-end operational amplifier and a fast analogue to digital converter. With this board, the user can experiment and implement specific applications, such as rain/no rain detection, hail detection, or drop energy. The design of the DisdroWing is publicly available and can also be purchased fully assembled.</p>

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Deteksi Bentuk Objek Bawah Tanah Menggunakan Pengolahan Citra B-Scan pada Ground Penetrating Radar (GPR)

TELKA - Telekomunikasi Elektronika Komputasi dan Kontrol ◽

10.15575/telka.v3i1.54 ◽

2017 ◽

Vol 3 (1) ◽

pp. 73-83

Author(s):

Rahmayati Alindra ◽

Heroe Wijanto ◽

Koredianto Usman

Keyword(s):

Signal Processing ◽

Ground Penetrating Radar ◽

Post Processing ◽

Data Survey ◽

Ground Penetrating

Ground Penetrating Radar (GPR) adalah salah satu jenis radar yang digunakan untuk menyelidiki kondisi di bawah permukaan tanah tanpa harus menggali dan merusak tanah. Sistem GPR terdiri atas pengirim (transmitter), yaitu antena yang terhubung ke generator sinyal dan bagian penerima (receiver), yaitu antena yang terhubung ke LNA dan ADC yang kemudian terhubung ke unit pengolahan data hasil survey serta display sebagai tampilan output-nya dan post processing untuk alat bantu mendapatkan informasi mengenai suatu objek. GPR bekerja dengan cara memancarkan gelombang elektromagnetik ke dalam tanah dan menerima sinyal yang dipantulkan oleh objek-objek di bawah permukaan tanah. Sinyal yang diterima kemudian diolah pada bagian signal processing dengan tujuan untuk menghasilkan gambaran kondisi di bawah permukaan tanah yang dapat dengan mudah dibaca dan diinterpretasikan oleh user. Signal processing sendiri terdiri dari beberapa tahap yaitu A-Scan yang meliputi perbaikan sinyal dan pendektesian objek satu dimensi, B-Scan untuk pemrosesan data dua dimensi dan C-Scan untuk pemrosesan data tiga dimensi. Metode yang digunakan pada pemrosesan B-Scan salah satunya adalah dengan teknik pemrosesan citra. Dengan pemrosesan citra, data survey B-scan diolah untuk didapatkan informasi mengenai objek. Pada penelitian ini, diterapkan teori gradien garis pada pemrosesan citra B-scan untuk menentukan bentuk dua dimensi dari objek bawah tanah yaitu persegi, segitiga atau lingkaran.

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