Ignoring all .py files in the examples folder

This is to prevent pre-compiled Python files from being uploaded by mistake

gnuradio/gr-dji_droneid/.gitignore

@@ -1,3 +1,4 @@
 cmake-build-debug
 build
 .idea
+examples/*.py

gnuradio/gr-dji_droneid/examples/README

@@ -1,3 +1,5 @@
-It is considered good practice to add examples in here to demonstrate the
-functionality of your OOT module. Python scripts, GRC flow graphs or other
-code can go here.
+The `autocorrelator.grc` graph is just a demonstration of how to detect DroneID frames without any OOT modules.
+It does still require the use of the GNU Radio module as there are functions in the OOT that are needed.  Just no
+normal OOT blocks required.
+
+This ended up being a lot faster than doing the coding by hand, so huzzah to the GNU Radio devs!

gnuradio/gr-dji_droneid/include/gnuradio/dji_droneid/utils.h

@@ -107,6 +107,24 @@ public:
      * @return Variance of the complex vector
      */
     static float variance(const std::complex<float> * samples, uint32_t sample_count);
+
+    /**
+     * Calculate the variance of a complex vector where the mean is not known to be zero
+     *
+     * This function is mostly the same as utils::variance_no_mean but does have to calculate the
+     * mean value of the input vector and subtract it from each sample, so this will take longer
+     * @param samples Vector of complex samples
+     * @return Variance of the complex vector
+     */
+    static float variance_vector(const std::vector<std::complex<float>> & samples);
+
+    /**
+     * Get the conjugate of the provided vector
+     * @param samples Vector of complex samples
+     * @return Conjugate of the input sample vector
+     */
+    static std::vector<std::complex<float>> conj_vector(const std::vector<std::complex<float>> & samples);
+
 private:
 };
 

gnuradio/gr-dji_droneid/lib/CMakeLists.txt

@@ -22,7 +22,7 @@ if(NOT dji_droneid_sources)
 endif(NOT dji_droneid_sources)
 
 add_library(gnuradio-dji_droneid SHARED ${dji_droneid_sources})
-target_link_libraries(gnuradio-dji_droneid gnuradio::gnuradio-runtime gnuradio-fft fftw3)
+target_link_libraries(gnuradio-dji_droneid gnuradio::gnuradio-runtime gnuradio-fft fftw3 gnuradio-blocks gnuradio-filter)
 target_include_directories(gnuradio-dji_droneid
     PUBLIC $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/../include>
     PUBLIC $<INSTALL_INTERFACE:include>
@@ -92,6 +92,7 @@ include(GrTest)
 #include_directories()
 # List all files that contain Boost.UTF unit tests here
 list(APPEND test_dji_droneid_sources
+        # Only tests that do not require MATLAB will live here
 )
 # Anything we need to link to for the unit tests go here
 list(APPEND GR_TEST_TARGET_DEPS gnuradio-dji_droneid)

gnuradio/gr-dji_droneid/lib/qa_utils.cc

@@ -145,6 +145,17 @@ struct TestFixture {
         return {output_samples.begin(), output_samples.end()};
     }
 
+    static std::vector<std::complex<float>> conj(const std::vector<std::complex<float>> & samples) {
+        matlab_engine->setVariable("samples", factory.createArray({1, samples.size()}, samples.begin(), samples.end()));
+        matlab_engine->eval(u"samples = single(conj(samples));");
+        const matlab::data::TypedArray<std::complex<float>> output_samples = matlab_engine->getVariable("samples");
+        matlab_engine->eval(u"clear samples");
+
+        BOOST_REQUIRE_EQUAL(output_samples.getNumberOfElements(), samples.size());
+
+        return {output_samples.begin(), output_samples.end()};
+    }
+
     static std::vector<std::complex<float>> create_test_vector(const uint32_t sample_count) {
         matlab_engine->setVariable("sample_count", factory.createScalar(static_cast<double>(sample_count)));
         matlab_engine->eval(u"samples = single(complex(randn(1, sample_count), randn(1, sample_count)));");
@@ -279,6 +290,20 @@ BOOST_AUTO_TEST_CASE(test_utils__variance) {
     }
 }
 
+BOOST_AUTO_TEST_CASE(test_utils__variance_vector) {
+    const uint32_t iters = 100;
+    const uint32_t length = 10000;
+
+    for (auto iter = decltype(iters){0}; iter < iters; iter++) {
+        const auto samples = create_test_vector(length);
+
+        const auto expected = var(samples);
+        const auto calculated = utils::variance_vector(samples);
+
+        BOOST_REQUIRE_CLOSE(expected, calculated, 0.002);
+    }
+}
+
 BOOST_AUTO_TEST_CASE(test_utils__variance_no_mean) {
     const uint32_t iters = 100;
     const uint32_t length = 10000;
@@ -293,6 +318,20 @@ BOOST_AUTO_TEST_CASE(test_utils__variance_no_mean) {
     }
 }
 
+BOOST_AUTO_TEST_CASE(test_utils__conj_vector) {
+    const uint32_t iters = 100;
+    const uint32_t length = 10000;
+
+    for (auto iter = decltype(iters){0}; iter < iters; iter++) {
+        const auto samples = create_test_vector(length);
+
+        const auto expected = conj(samples);
+        const auto calculated = utils::conj_vector(samples);
+
+        BOOST_REQUIRE_EQUAL_COLLECTIONS(expected.begin(), expected.end(), calculated.begin(), calculated.end());
+    }
+}
+
 BOOST_AUTO_TEST_SUITE_END()
 
 } /* namespace dji_droneid */

gnuradio/gr-dji_droneid/lib/utils.cc

@@ -172,5 +172,25 @@ float utils::variance(const std::complex<float> * const samples, const uint32_t
     return total / static_cast<float>(sample_count - 1);
 }
 
+std::vector<std::complex<float>>
+utils::conj_vector(const std::vector<std::complex<float>>& samples)
+{
+    std::vector<std::complex<float>> output(samples.size());
+    for (auto idx = decltype(samples.size()){0}; idx < samples.size(); idx++) {
+        const auto & sample = samples[idx];
+        output[idx] = {
+            sample.real(),
+            -sample.imag()
+        };
+    }
+
+    return output;
+}
+
+float utils::variance_vector(const std::vector<std::complex<float>>& samples)
+{
+    return variance(&samples[0], samples.size());
+}
+
 } /* namespace dji_droneid */
 } /* namespace gr */

gnuradio/gr-dji_droneid/python/dji_droneid/bindings/docstrings/utils_pydoc_template.h

@@ -40,3 +40,18 @@ static const char* __doc_gr_dji_droneid_utils_create_zc = R"doc()doc";
 
 
 static const char* __doc_gr_dji_droneid_utils_get_cyclic_prefix_lengths = R"doc()doc";
+
+
+static const char* __doc_gr_dji_droneid_utils_mean_fast = R"doc()doc";
+
+
+static const char* __doc_gr_dji_droneid_utils_variance_no_mean = R"doc()doc";
+
+
+static const char* __doc_gr_dji_droneid_utils_variance = R"doc()doc";
+
+
+static const char* __doc_gr_dji_droneid_utils_variance_vector = R"doc()doc";
+
+
+static const char* __doc_gr_dji_droneid_utils_conj_vector = R"doc()doc";

gnuradio/gr-dji_droneid/python/dji_droneid/bindings/utils_python.cc

@@ -14,7 +14,7 @@
 /* BINDTOOL_GEN_AUTOMATIC(0)                                                       */
 /* BINDTOOL_USE_PYGCCXML(0)                                                        */
 /* BINDTOOL_HEADER_FILE(utils.h)                                        */
-/* BINDTOOL_HEADER_FILE_HASH(341b0421657c63a408a05e68560d4ff8)                     */
+/* BINDTOOL_HEADER_FILE_HASH(2b797448fb8ea6ebcdf63ff38c33eb3c)                     */
 /***********************************************************************************/
 
 #include <pybind11/complex.h>
@@ -78,5 +78,36 @@ void bind_utils(py::module& m)
                     py::arg("sample_rate"),
                     D(utils, get_cyclic_prefix_lengths))
 
+
+        .def_static("mean_fast",
+                    &utils::mean_fast,
+                    py::arg("samples"),
+                    py::arg("sample_count"),
+                    D(utils, mean_fast))
+
+
+        .def_static("variance_no_mean",
+                    &utils::variance_no_mean,
+                    py::arg("samples"),
+                    py::arg("sample_count"),
+                    D(utils, variance_no_mean))
+
+
+        .def_static("variance",
+                    &utils::variance,
+                    py::arg("samples"),
+                    py::arg("sample_count"),
+                    D(utils, variance))
+
+
+        .def_static("variance_vector",
+                    &utils::variance_vector,
+                    py::arg("samples"),
+                    D(utils, variance_vector))
+
+
+        .def_static(
+            "conj_vector", &utils::conj_vector, py::arg("samples"), D(utils, conj_vector))
+
         ;
 }