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The paper presents a new parallel laser ranging technology of array type which adopts multi-channel frequency division
multiplexing modulation to realize multi-point synchronous measurement. The DDS (direct digital synthesis) technology
is used to produce the parallel sine wave signals needed to realize frequency division multiplexing modulation on the
lasers of array. The signals are produced by DDS chips under the control of DSP processor. Because phase has a great
effect on the measurement precision of the system and the commonly used digital phase detection method - FFT
algorithm has its own drawbacks, such as spectral leakage, "non-synchronous sampling" etc. which cause errors, so the
all-phase FFT is introduced here to remedy these defects. The phase- spectrum value at main spectral line can be directly
viewed as the original phase without any correcting measures. The paper elaborates the realization of parallel laser
modulation, laser detecting, mixing, synchronous sampling and high-accuracy phase detection using this technology,
analyzes the factors which cause errors. The results of preliminary experiment and simulation indicate that the parallel
laser ranging technology of array type could be used to realize high-speed high-accuracy parallel measurement.
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