The only Canadian stores I have routinely made purchases from were Focus Scientific, Ottawa (I'll miss the store manager, Tristan -- the engine behind their superior customer service) and La Maison De L'Astronomie, Montreal. I did buy a barlow from Kahn Scope in Toronto in 2007, so I h...
DPSK stores the phase information in the relative phase of adjacent symbols. Phase fluctuation of neighboring symbols is determined by the same atmospheric turbulence, and the change between them is consistent. Therefore, the bit error rate (BER) caused by inter-symbol interference is reduced, and...