Modern avionics equipment, such as superresolution direction-finding s
ystems (frequency band 0.3 to 3 MHz), now require resolutions greater
than 15 bits. Oversampled analog-to-digital converter architectures of
fer a means of exchanging resolution in time for that in amplitude and
represent an attractive approach to implementing precision converters
without the need for complex precision analog circuits. Using oversam
pling techniques based on sigma-delta (Sigma Delta) modulation, a conv
enient trade-off exists between sampling rate and resolution, One of t
he major advantages of integrated optics is the capability to efficien
tly couple wideband signals into the optical domain. Typically, Sigma
Delta processors require simple and relatively low precision analog co
mponents and thus are well suited to integrated optical implementation
s. The current Sigma Delta methodology is reviewed and the design of t
he single-bit, integrated optical Sigma Delta modulator is presented.
Simulation results for both first- and second-order architectures are
presented by evaluating the transfer characteristics numerically. A 16
-bit f(0)=1 MHz design (oversampling ratio of 132) is also quantified.
(C) 1996 Society of Photo-Optical Instrumentation Engineers.