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Pulse density modulation
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Pdm, английский
- Programed depot maintenance
- Pulse-duration modulation
- Possible duplicate message
- Product data management
- Project development manager
- Product data management (управление данными о продукции)
Широтно-импульсная модуляция, шим. см. pwm, русский
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Pulse modulation, английский
A method akin to digital modulation where the intensity of a carrier is modulated between two states, either maximum or zero. if the pulse width is small and the repetition rate slow, the peak power in the pulse can be vastly above that of the mean power. for instance, if a pulse of 1 nanosecond (10-9 sec) duration is transmitted every second, then the peak power is 1 billion times or 109 (90 db) above the mean power. it is very easy for this "lighthouse" laser beacon to outshine a star during each brief flash. during each flash, the rate at which photons arrive at the receiver is much higher than from the stellar or sky backgrounds. for the example given, this ratio can be as high as 10 million times.
Pdm, английский
- Programed depot maintenance
- Pulse-duration modulation
- Possible duplicate message
- Product data management
- Project development manager
- Product data management (управление данными о продукции)
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