A method of creating an image from an acoustic waveform in an acoustic imaging device, comprising: setting a transmit/receive switch in the acoustic imaging device into a transmit mode to transmit an acoustic waveform toward a target; in transmitting the acoustic waveform, synthesizing (153, 154), in one or more waveform synthesizers, a plurality of substantially orthogonal coded waveforms that form a composite waveform as the transmitted acoustic waveform toward the target, wherein the composite waveform is represented in the time domain as a complex number, given by W t = ∑ k ∑ n A nk e j 2 πnf 0 t + φ nk + C n U t − kT wherein W is comprised of M individual orthogonal waveforms, T represents the transmit period within a time epoch, f 0 represents the fundamental chip frequency, such that f 0 =1/NT, Nf 0 is the maximum frequency and (M-N+1)f 0 is the minimum frequency, n represents a sequence of positive integers from N-M+1 to N, the waveform repetition frequency is 1/T f, with T f being the duration of a time epoch, U(x)=1 for o≤x≤T, Φ nk represents the frequency chip phase term of the n th chip in the k th time epoch, and A nk is the amplitude of the n th chip in the k th time epoch, and C n is an additive phase term being a number between o and 2π, wherein the amplitude A nk or the phase φ nk for a particular frequency chip is determined as a single value for that frequency chip during a particular time epoch and assigned a different single value in subsequent time epochs; setting the transmit/receive switch in the acoustic imaging device into a receive mode to receive a returned acoustic waveform that returns from at least part of the target; converting the received returned acoustic waveform from analog format to digital format as a received composite waveform comprising information of the target; and processing the received composite waveform to produce an image of at least part of the target. setting a transmit/receive switch in the acoustic imaging device into a transmit mode to transmit an acoustic waveform toward a target; in transmitting the acoustic waveform, synthesizing (153, 154), in one or more waveform synthesizers, a plurality of substantially orthogonal coded waveforms that form a composite waveform as the transmitted acoustic waveform toward the target, wherein the composite waveform is represented in the time domain as a complex number, given by W t = ∑ k ∑ n A nk e j 2 πnf 0 t + φ nk + C n U t − kT wherein W is comprised of M individual orthogonal waveforms, T represents the transmit period within a time epoch, f 0 represents the fundamental chip frequency, such that f 0 =1/NT, Nf 0 is the maximum frequency and (M-N+1)f 0 is the minimum frequency, n represents a sequence of positive integers from N-M+1 to N, the waveform repetition frequency is 1/T f, with T f being the duration of a time epoch, U(x)=1 for o≤x≤T, Φ nk represents the frequency chip phase term of the n th chip in the k th time epoch, and A nk is the amplitude of the n th chip in the k th time epoch, and C n is an additive phase term being a number between o and 2π, wherein the amplitude A nk or the phase φ nk for a particular frequency chip is determined as a single value for that frequency chip during a particular time epoch and assigned a different single value in subsequent time epochs; setting the transmit/receive switch in the acoustic imaging device into a receive mode to receive a returned acoustic waveform that returns from at least part of the target; converting the received returned acoustic waveform from analog format to digital format as a received composite waveform comprising information of the target; and processing the received composite waveform to produce an image of at least part of the target.