Contents
How is noise equivalent power measured?
Noise can be equivalently given on both sides of the detector either as a voltage noise density vn at the output (in V/√Hz) or as a Noise Equivalent Power (NEP) at the input (in W/√Hz). Both quantities are related by: NEP=vn/G, where G is the detector gain in V / W.
How is Detectivity calculated?
The specific detectivity D* is the detectivity normalized to a unit detector area (1 m2) and detection bandwidth (1 Hz); one can calculate it by multiplying the detectivity with the square root of the product of detector area (in square centimeters) and the detector bandwidth (in Hz).
What is unit of responsivity?
Units of responsivity are amperes per watts (A W−1) or volts per watts (V W−1). When the definition of the responsivity is expanded to include the frequency dependence and the wavelength (spectral) dependence, the responsivity is known as the spectral responsivity R(λ, f).
What is noise types of noise?
Among the most common types of noise are electronic noise, thermal noise, intermodulation noise, cross-talk, impulse noise, shot noise and transit-time noise.
How to calculate thermal noise power in dBm units?
Noise power is based on the thermal noise power at the input of the system, along with system gain and noise figure: Multiply by 1000 to obtain milliwatts and then convert to dBm units: Now that we have the thermal noise at the input, add the system gain and the additional noise added by the system (the NF) to get the noise power at the output:
What are the noise sources in a photodiode system?
There are many noise sources for a photodiode detection system such as Johnson noise from the load resistor, shot noise from the incident light, and voltage noise from the measuring instrument. The dominant noise sources are dependent on the system configuration.
How is the responsivity of a photodiode determined?
In other words, it is measure of the effectiveness of conversion of light power into electric current. It varies with the wavelength of incident light, applied reverse bias and temperature.
How does the saturation limit of a photodiode depend?
•The saturation limit of a photodiode is dependent on the reverse bias voltage and the load resistance. •The noise floor of a photodiode detection system depends not only on the NEP of the diode but also significantly on the load resistance.