What is q-factor in optical communication?
What is q-factor in optical communication?
The Q-factor suggests the minimum signal-to-noise ratio (SNR) required to obtain a specific BER for a given signal. OSNR is measured in decibels. The higher the bit rate, the higher the OSNR ratio required. For OC-192 transmissions, the OSNR should be at least 27 to 31 dB compared to 18 to 21 dB for OC-48.
What is Q-factor in communication?
The Q or quality factor is a dimensionless number and it describes the damping in the circuit. It also provides an indication of the resonator’s bandwidth relative to its centre frequency. Simple formulas relate the losses and bandwidth to the Q.
How do you measure the BER and Q-factor in digital transmission?
As Omar says, Q is usually defined as the eye opening (difference between upper and lower signal levels) divided by the sum of the individual noise standard deviations on the two levels. BER ~ 1.3 10-12 for Q=7, BER ~ 10-9 for Q=6, and BER ~ 1.35 10-3 for Q=3.
What is optical signal to noise ratio?
Optical signal to noise ratio (OSNR) is an important figure of merit used in fiber link planning. It is the ratio of signal power to noise power, over a specific spectral bandwidth, at any point in an optical link. Noise power can be defined as any undesirable signal interference.
What is optical Q?
Optical systems The optical Q is equal to the ratio of the resonant frequency to the bandwidth of the cavity resonance. The average lifetime of a resonant photon in the cavity is proportional to the cavity’s Q.
What is BER and Q factor?
The Q-factor provides a qualitative description of the receiver performance because it is a function of the signal to noise ratio (optical). The Q-factor suggests the minimum SNR required to obtain a specific BER for a given signal. As we can see, the higher the value of Q-factor, the better the BER.
What is SNR dB?
In terms of definition, SNR or signal-to-noise ratio is the ratio between the desired information or the power of a signal and the undesired signal or the power of the background noise. In other words, SNR is the ratio of signal power to the noise power, and its unit of expression is typically decibels (dB).
What is a good quality factor?
Good high-Q capacitors can have a Q factor value of over 10,000 at 1MHz and over 1,000 at 100MHz, while standard capacitors can have a Q factor as low as 50 at 1kHz. Such capacitors can be used at frequencies of up to 20GHz, which is sufficient for most RF applications.
