Algorithm to get PVT without the time mark from the navigation message

Hi there,

I am looking for an algorithm to compute PVT without the navigation
message (time mark, ephemeris, Iono model etc.) The Ephemeris, Iono
model will be achieved from IGS products. Could anybody please provide
me some useful information (such as a link to patents claimed) for such
an algorithm? The algorithm should generate PVT with biased pseudoranges
(no time mark from either the navigation message or the cellular network).

It would be best if the algorithm only needs a few millisecond of GPS
data, such as BGPS.

Thank you!

Johnson