Sequential extraction and recognition of pulse group structure for multi‐function radar

Abstract

The structure design and switching regulation of pulse groups in multi‐function radars (MFRs) are closely related to the work mode. The sequential extraction and recognition of MFR pulse group structure is a fundamental task to analysing and interpreting the work modes and behaviour intentions of an MFR. In this study, the temporal structure of MFR pulse group is expressed hierarchically, which is intensively modelled based on regular grammar. Besides, a corresponding hierarchical automaton is established to sequentially extract and recognise the MFR pulse group structure in pulse train. The hierarchical automaton used for pulse group recognition has a two‐layer structure. The bottom layer of the hierarchical automaton realises the sequential input of pulses and recognition of pulse subgroups, and the sequential input of pulse subgroups and recognition of pulse groups are realised at the top layer. The simulation results demonstrate that the proposed method performs satisfyingly in recognising the pulse group structure and is robust to not only pulse noises but also to the emitter number and pulse group scale.

Reconstruction of Radar Pulse Repetition Pattern via Semantic Coding of Intercepted Pulse Trains

“…For instance, when pulse trains of {a, b, c, a, b, c, ..., a, b, c} and {a, c, b, a, c, b, ..., a, c, b} from two radars are intercepted, the typical PRI value set {a, b, c} easily misjudges the two radars as one, while the reconstructed PRI patterns [a, b, c] and [a, c, b] with high diemnsions can directly distinguish the two radars. Furthermore, the high-dimensional temporal characteristic can act as valuable information for deinterleaving complex signals with complex PRI modulation [1] and pulse group recognition [2] of multi-function radars.…”

“…It is a structural characteristic with high dimension in the pulse train, including the particular values, ordering and switching law of PRIs. Among them, PRI values reflect the detection distance and platform of emitters to a certain extent; The ordering reflects signals' timing structure, which is required by online deinterleaving [1] and recognition [2]; The switching law, also known as PRI modulation type, indicates working modes of radar. For conventional radars using fixed and staggered PRIs [3], a complete PRI pattern is the basic temporal structure of pulses that repeats periodically all through the pulse train.…”

“…PRI pattern reconstruction refers to extracting the high-dimensional timing feature from the intercepted pulse train without priori information. Its output has wide adaptability for signal processing tasks such as deinterleaving [1,[4][5] and recognition [2,[7][8][10][11]. In the field of pulse deinterleaving, common methods [4][5][6] exploit discrete PRI values obtained mainly by statistics to deinterleave pulse trains.…”