Homodyne and autodyne configurations of short-range radar systems

The processes of useful signal formation in the short-range radar systems constructed on the heterodyne, homodyne and autodyne principles are considered. The mathematical fundamentals of the fulfilled analysis are described in brief. It is shown that the autodyne configuration is much more complicated for the examination compared to the heterodyne and homodyne configurations due to the necessity of taking into account its own re-reflected signal. To simplify the theoretical analysis, the examination of the autodyne effect is performed under an assumption of reflected signal smallness. The comparison results of the considered configurations, which show that the homodyne and autodyne signal processing in the usual Doppler short-range radar turns out similar, are given. However, the autodyne short-range radar configuration itself has its own specific peculiarities, which should be taken into consideration in practice. It is proved that in the autodyne configuration one can meet the accompanying frequency modulation of the probing oscillation. It appears even at the absence of the forced frequency modulation, which is widely used to improve the short-range radar noise immunity. It is found out that this accompanying frequency modulation at weak reflected signals does not affect noticeably on the autodyne converter operation. The main theoretical conclusions of this paper are in the good conformity with the published results

HOMODYNE AND AUTODYNE CONFIGURATIONS OF SHORT-RANGE RADAR SYSTEMS

The processes of useful signal formation in the short-range radar systems constructed on the heterodyne, homodyne and autodyne principles are considered. The mathematical fundamentals of the fulfilled analysis are described in brief. It is shown that the autodyne configuration is much more complicated for the examination compared to the heterodyne and homodyne configurations due to the necessity of taking into account its own re-reflected signal. To simplify the theoretical analysis, the examination of the autodyne effect is performed under an assumption of reflected signal smallness. The comparison results of the considered configurations, which show that the homodyne and autodyne signal processing in the usual Doppler short-range radar turns out similar, are given. However, the autodyne short-range radar configuration itself has its own specific peculiarities, which should be taken into consideration in practice. It is proved that in the autodyne configuration one can meet the accompanying frequency modulation of the probing oscillation. It appears even at the absence of the forced frequency modulation, which is widely used to improve the short-range radar noise immunity. It is found out that this accompanying frequency modulation at weak reflected signals does not affect noticeably on the autodyne converter operation. The main theoretical conclusions of this paper are in the good conformity with the published results

SSoelvsten/adiar: v2.0.0-beta.5

New Features Functional Bridge: Fully generalised and committed to the use of functions to bridge between Adiar and the user's code (as was started in v2.0-beta.2). To this end, Adiar now provides the types predicate and generator to pass information into Adiar and consumer to pass information back out again. All functions of v1.x that used some file, e.g. bdd_restrict, zdd_onset, bdd_varprofile etc. all now provide one (or more) of these functions instead. Execution Policy: Each algorithm (when relevant) has been overloaded with an exec_policy as its first argument. This class provides a thread-safe way of passing options into an algorithm, e.g. whether the algorithm should use internal or external memory data structures. This replaces the use of the globally set enum values, e.g. memory_mode. bdd_top(), bdd_bot(), zdd_top(...), and zdd_bot(...): Provide a uniform interface for getting the top and the bot value of the lattice. This provides a more uniform and interchangeable interface between BDDs and ZDDs where you do not need to think about the reduction rules. Optimisations bdd_satmin and bdd_satmax Stores the intermediate result in an internal memory stack (since it can at most be 8 MiB in size) rather than writing it out to disk. This should improve their performance slightly. Breaking Changes The function overloads with an auxiliary file as an input, e.g. bdd_restrict, zdd_onset, bdd_varprofile, have been removed in favour of the new functional input instead. The enums memory_mode, access_mode, and quantify_mode have been removed in favour of using the new Execution Policy. Removed the functions bdd_counter and zdd_sized_set. They may be added anew, assuming someone sends in a feature request. Fixed inconsistency of naming scheme in predicates. For example, the function is_true(const bdd &) has been renamed to bdd_istrue(const bdd&) to be consistent with the rest of the API. Removed the map_pair class introduced in v2.0-beta.2 as it has become redundant with the simpler function interface. Contributors Steffan Sølvsten ( @SSoelvsten