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Table 3 Parameters of the QKD model for a conservative source performance. Note that we consider two cases: \(\tau = 1~\mbox{ns}\) and \(\mu = 0.1\), corresponding to a pair production of \(10^{8}~\mbox{s}^{-1}\), and \(\tau = 200~\mbox{ps}\) and \(\mu = 0.06\), which corresponds to \(R_{\text{pair}} = 3 \cdot 10 ^{8}~\mbox{s} ^{-1}\)

From: Nanobob: a CubeSat mission concept for quantum communication experiments in an uplink configuration

q basis reconciliation factor 0.5  
f(E) bidirectional error correction function 1.22  
τ coincidence time window 1 (0.2) ns
μ average number of photons per pulse 0.1 (0.06)  
\(D_{A}\) OGS dark count rate per detector 100 cps
\(D_{B}\) satellite dark count rate per detector ≥100 cps
B satellite background count rate 400 cps
\(N_{\mathrm{det}}\) number of detectors 4  
PDE Photon Detection Efficiency of satellite single photon detectors [40] 0.4  
\(T_{\mathrm{optics}}\) satellite receiver optical transmission 0.8  
\(\eta _{A}\) OGS overall detection efficiency [44] 0.6  
\(\eta _{B}\) \(\eta _{B} = T_{\mathrm{optics}} \cdot \mbox{PDE} \cdot 10^{-A/10}\), with A the quantum channel link attenuation in dB   
\({e}_{0}\) error probability of dark- and background counts 0.5  
\({e}_{\mathrm{d}}\) error probability of photon arriving on wrong detector (polarization error) 0.01