20.500.12556/DKUM-87733 Measurements of Small Frequency Differences by Dual Mode 4 MHz Quartz Sensors We proposed a method for measuring frequency differences of the order of a few Hz with an experimental error lower than 0.0001% by using two 4 MHz quartz oscillators, the frequencies of which are very close (a few 10 Hz difference) due to the dual mode operation (differential mode with two temperature-compensated signal frequencies or a mode with one signal and one reference frequency). We compared the existing methods for measuring frequency differences with the new method which is based on counting the number of transitions through zero within one beat period of the signal. The measuring procedure requires equal experimental conditions (temperature, pressure, humidity, parasitic impedances etc.) for both quartz oscillators. To ensure equal resonant conditions for oscillation two quartz crystals are needed, which form a temperature pair. The frequencies and resonant conditions of both oscillators must be almost equal, which is achieved by an external inductance or capacitance. In such a way, we minimized all the external effects and ensured highly stable oscillations and high sensitivity of the differential sensors. The counter detects one beat period by an external gate signal former. By using the method of counting transitions through zero within one beat period, we reduced the measuring error by three orders of magnitude, compared to the existing methods. small frequency difference measurement temperature-compensated quartz sensors differential sensors quartz oscillators transitions-through-zero method majhne frekvence meritev senzorji oscilatorji true false true MDPI Angleški jezik Slovenski jezik https://www.mdpi.com/journal/sensors © 2023 by the author Članek v reviji 2024-03-26 15:37:36 2024-03-26 15:49:45 2024-05-24 07:58:16 0000-00-00 00:00:00 2023 0 0 Str. 1-11 Št. 6, št. članka 3220 Letn. 23 17 March 2023 0000-00-00 Zaloznikova Objavljeno NiDoloceno 2023-02-02 2023-03-15 2023-03-17 621.317 145579779 10.3390/s23063220 1424-8220 Matko-2023-Measurements_of_Small_Frequency_Dif.pdf Matko-2023-Measurements_of_Small_Frequency_Dif.pdf 1 5F8F76F43233145DFE886A1112452B92 befc584e74392f4708e9d1373f0671a9918b058d165b239bae8bf7503c90167c a4e91582-eb7f-11ee-adef-00155d000105 https://dk.um.si/Dokument.php?lang=slv&id=177424 https://www.mdpi.com/1424-8220/23/6/3220 0 c7d21117-eb7f-11ee-adef-00155d000105 https://dk.um.si/Dokument.php?lang=slv&id=177425 Fakulteta za elektrotehniko, računalništvo in informatiko 0 0 0