--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/spandsp-0.0.3/spandsp-0.0.3/src/spandsp/dds.h	Fri Jun 25 16:00:21 2010 +0200
@@ -0,0 +1,145 @@
+/*
+ * SpanDSP - a series of DSP components for telephony
+ *
+ * dds.h
+ *
+ * Written by Steve Underwood <steveu@coppice.org>
+ *
+ * Copyright (C) 2003 Steve Underwood
+ *
+ * All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ * $Id: dds.h,v 1.9 2006/10/24 13:45:28 steveu Exp $
+ */
+
+/*! \file */
+
+#if !defined(_DDS_H_)
+#define _DDS_H_
+
+#include "complex.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/*! \brief Find the phase rate value to achieve a particular frequency.
+    \param frequency The desired frequency, in Hertz.
+    \return The phase rate which while achieve the desired frequency.
+*/
+int32_t dds_phase_rate(float frequency);
+
+float dds_frequency(int32_t phase_rate);
+
+/*! \brief Find the scaling factor needed to achieve a specified level in dBm0.
+    \param level The desired signal level, in dBm0.
+    \return The scaling factor.
+*/
+int dds_scaling_dbm0(float level);
+
+int dds_scaling_dbov(float level);
+
+/*! \brief Find the amplitude for a particular phase.
+    \param phase The desired phase 32 bit phase.
+    \return The signal amplitude.
+*/
+int16_t dds_lookup(uint32_t phase);
+
+/*! \brief Find the amplitude for a particular phase offset from an accumulated phase.
+    \param phase_acc The accumulated phase.
+    \param phase_offset The phase offset.
+    \return The signal amplitude.
+*/
+int16_t dds_offset(uint32_t phase_acc, int32_t phase_offset);
+
+/*! \brief Generate an integer tone sample.
+    \param phase_acc A pointer to a phase accumulator value.
+    \param phase_rate The phase increment to be applied.
+    \return The signal amplitude, between -32767 and 32767.
+*/
+int16_t dds(uint32_t *phase_acc, int32_t phase_rate);
+
+/*! \brief Generate an integer tone sample, with modulation.
+    \param phase_acc A pointer to a phase accumulator value.
+    \param phase_rate The phase increment to be applied.
+    \param scale The scaling factor.
+    \param phase The phase offset.
+    \return The signal amplitude.
+*/
+int16_t dds_mod(uint32_t *phase_acc, int32_t phase_rate, int scale, int32_t phase);
+
+/*! \brief Generate a complex integer tone sample.
+    \param phase_acc A pointer to a phase accumulator value.
+    \param phase_rate The phase increment to be applied.
+    \return The complex signal amplitude, between -32767 and 32767.
+*/
+icomplex_t dds_complex(uint32_t *phase_acc, int32_t phase_rate);
+
+/*! \brief Generate a complex integer tone sample, with modulation.
+    \param phase_acc A pointer to a phase accumulator value.
+    \param phase_rate The phase increment to be applied.
+    \param scale The scaling factor.
+    \param phase The phase offset.
+    \return The complex signal amplitude.
+*/
+icomplex_t dds_complex_mod(uint32_t *phase_acc, int32_t phase_rate, int scale, int32_t phase);
+
+int32_t dds_phase_ratef(float frequency);
+
+float dds_frequencyf(int32_t phase_rate);
+
+float dds_scaling_dbm0f(float level);
+
+float dds_scaling_dbovf(float level);
+
+/*! \brief Generate a floating point tone sample.
+    \param phase_acc A pointer to a phase accumulator value.
+    \param phase_rate The phase increment to be applied.
+    \return The signal amplitude, between -32767 and 32767.
+*/
+float ddsf(uint32_t *phase_acc, int32_t phase_rate);
+
+/*! \brief Generate a floating point tone sample, with modulation.
+    \param phase_acc A pointer to a phase accumulator value.
+    \param phase_rate The phase increment to be applied.
+    \param scale The scaling factor.
+    \param phase The phase offset.
+    \return The signal amplitude.
+*/
+float dds_modf(uint32_t *phase_acc, int32_t phase_rate, float scale, int32_t phase);
+
+/*! \brief Generate a complex floating point tone sample.
+    \param phase_acc A pointer to a phase accumulator value.
+    \param phase_rate The phase increment to be applied.
+    \return The complex signal amplitude, between -32767 and 32767.
+*/
+complexf_t dds_complexf(uint32_t *phase_acc, int32_t phase_rate);
+
+/*! \brief Generate a complex floating point tone sample, with modulation.
+    \param phase_acc A pointer to a phase accumulator value.
+    \param phase_rate The phase increment to be applied.
+    \param scale The scaling factor.
+    \param phase The phase offset.
+    \return The complex signal amplitude.
+*/
+complexf_t dds_complex_modf(uint32_t *phase_acc, int32_t phase_rate, float scale, int32_t phase);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
+/*- End of file ------------------------------------------------------------*/