Initial import

demodulator.h

@@ -0,0 +1,80 @@
+/* 
+ * File:   demodulator.h
+ */
+
+#ifndef DEMODULATOR_H
+#define	DEMODULATOR_H
+
+#ifdef __XC16
+#include <dsp.h>
+#else
+typedef int16_t _Q0_15;
+typedef int32_t _Q15_16;
+
+typedef _Q0_15 _Q15;
+typedef _Q15_16 _Q16;
+
+typedef int16_t fractional;
+#endif
+
+#include <stdint.h>
+#include "modem_types.h"
+
+#define MAX_PHASE_SKEW                  10000L
+#define ADC_MAX_AMPLITUDE               10000L
+
+typedef struct {
+    fractional frequency;
+    fractional phase;
+    fractional amplitude;
+} detector_symbol;
+
+extern detector_symbol detector_constellation[MAX_MODULATION_ALPHABET_SIZE], symbol_error, min_symbol_distance;
+
+// TODO 
+
+typedef struct {
+    uint8_t buffer[MAX_SYMBOL_BUFFER_SIZE];
+    uint8_t index;
+    uint8_t length;
+} symbol_buffer;
+
+// extern symbol_buffer rx_symbol_buffer;
+
+// buffer dei simboli
+extern uint8_t rx_symbol_buffer[MAX_SYMBOL_BUFFER_SIZE];
+extern uint8_t rx_symbol_buffer_index, rx_symbol_buffer_lenght;
+
+extern uint8_t rx_sample_buffers_buffer[MAX_BUFFERS_PER_SYMBOL], rx_sample_buffer_index;
+
+extern uint8_t volatile process_input_sample_buffer;
+
+// zona del simbolo da esaminare:
+extern uint8_t rx_symbol_detected_part_offset, rx_symbol_detected_part_length;
+
+// NCO
+extern fractional tanlock_nco_rotor_inc;
+
+#ifdef __DSP_LIB__
+extern FIRStruct ph_det_lpFilterI, ph_det_lpFilterQ, ph_det_lpFilterFreq;
+#endif
+
+void demodulator_setup(void);
+void demodulator_sample_buffer_demodulate(fractional *buffer, detector_symbol* outsymbol);
+
+symbol find_constellation_center_values(symbol *constellation);
+int16_t get_angular_frequency(uint16_t frequency);
+void demodulator_prepare_constellation_symbols(symbol *constellation, detector_symbol *demod_constellation);
+detector_symbol demodulator_find_min_symbol_distance(detector_symbol *demod_constellation);
+uint8_t demodulator_most_frequent_value(uint8_t *serie, uint8_t range, uint8_t len);
+uint8_t demodulator_find_nearest_symbol(detector_symbol *in_symbol, detector_symbol *target_constellation, detector_symbol *moderror);
+
+fractional demodulator_phase_detector(fractional sig_in);
+fractional demodulator_frequency_detector(fractional phase);
+
+fractional _Q15atan2circle(fractional Y, fractional X);
+void FIR_init(void);
+
+
+#endif	/* DEMODULATOR_H */
+