Added header for receiver-module

module/src/receiver.pxd

+# cython: language_level=3
+# distutils: language=c++
+
+include "config.pxd"
+
+cdef extern from "receiver.h":
+    ctypedef struct ring_buffer:
+        int index
+        float data[N_SENSORS][BUFFER_LENGTH]
+
+    void write_buffer(ring_buffer *rb, float *frame);
+    void offset_ring_buffer(ring_buffer *rb);