公开(公告)号：EP0155776A1

公开(公告)日：1985-09-25

申请号：EP85301261.5

申请日：1985-02-25

申请人： STC PLC

发明人： Wong, Andrew Chi-Chung ,  Fearnhead, Graham Roy ,  Gale, Simon John

IPC分类号： G01S5/14 ,  G01S11/00

CPC分类号： G01S19/29

摘要： A NAVSTAR receiver in which the received signals are processed to produce digitised quadrature signals (l,Q) at zero i.f. Baseband phasor rotation to effect Doppler tracking in the receiver loop is accomplished by deriving digital signals representing sin wT and cos wT for the required rotation angle wT, multiplying the quadrature signals separately and summing the outputs according to the algorithm I' = I cos ωT + Q sin ωT and Q 1 = Q cos ωT - | sin ωT, where |& Q are the digitised quadrature signals.

公开(公告)号：EP0196179A3

公开(公告)日：1988-11-23

申请号：EP86301666

申请日：1986-03-10

申请人： STC PLC

发明人： Gale, Simon John

IPC分类号： H03H17/08 ,  G01S05/14

CPC分类号： H03H17/08 ,  G01S19/29

摘要： A method of effecting phase rotation of a digital signal by applying said digital signal as partial address signals for a look-up table in a memory together with rotation control signals forming additional address signals whereby the memory output represents the phase rotated signal, characterised in that each input vector is modified so that points representing digitised input vector values plotted on a rectangular coordinate grid are transformed to lie on an alternative coordinate system and the rotated vectors are retransformed and requantised to a digital output.