1 files changed, 107 insertions, 0 deletions
diff --git a/Transceiver52M/Channelizer.cpp b/Transceiver52M/Channelizer.cpp
new file mode 100644
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+++ b/Transceiver52M/Channelizer.cpp
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+/*
+ * Polyphase channelizer
+ * 
+ * Copyright (C) 2012-2014 Tom Tsou <tom@tsou.cc>
+ * Copyright (C) 2015 Ettus Research LLC
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * 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 Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ * See the COPYING file in the main directory for details.
+ */
+
+#include <stdlib.h>
+#include <math.h>
+#include <assert.h>
+#include <string.h>
+#include <cstdio>
+
+#include "Channelizer.h"
+
+extern "C" {
+#include "fft.h"
+#include "convolve.h"
+}
+
+static void deinterleave(const float *in, size_t ilen,
+			 float **out, size_t olen, size_t m)
+{
+	size_t i, n;
+
+	for (i = 0; i < olen; i++) {
+		for (n = 0; n < m; n++) {
+			out[m - 1 - n][2 * i + 0] = in[2 * (i * m + n) + 0];
+			out[m - 1 - n][2 * i + 1] = in[2 * (i * m + n) + 1];
+		}
+	}
+}
+
+size_t Channelizer::inputLen() const
+{
+	return blockLen * m;
+}
+
+size_t Channelizer::outputLen() const
+{
+	return blockLen;
+}
+
+float *Channelizer::outputBuffer(size_t chan) const
+{
+	if (chan >= m)
+		return NULL;
+
+	return hInputs[chan];
+}
+
+/* 
+ * Implementation based on material found in:
+ *
+ * "harris, fred, Multirate Signal Processing, Upper Saddle River, NJ,
+ *     Prentice Hall, 2006."
+ */
+bool Channelizer::rotate(const float *in, size_t len)
+{
+	size_t hSize = 2 * hLen * sizeof(float);
+
+	if (!checkLen(blockLen, len))
+		return false;
+
+	deinterleave(in, len, hInputs, blockLen, m);
+
+	/* 
+	 * Convolve through filterbank while applying and saving sample history 
+	 */
+	for (size_t i = 0; i < m; i++) {
+		memcpy(&hInputs[i][2 * -hLen], hist[i], hSize);
+		memcpy(hist[i], &hInputs[i][2 * (blockLen - hLen)], hSize);
+
+		convolve_real(hInputs[i], blockLen,
+			      subFilters[i], hLen,
+			      hOutputs[i], blockLen,
+			      0, blockLen, 1, 0);
+	}
+
+	cxvec_fft(fftHandle);
+
+	return true;
+}
+
+/* Setup channelizer paramaters */
+Channelizer::Channelizer(size_t m, size_t blockLen, size_t hLen)
+	: ChannelizerBase(m, blockLen, hLen)
+{
+}
+
+Channelizer::~Channelizer()
+{
+}