diff --git a/openbsc/tests/Makefile.am b/openbsc/tests/Makefile.am
index 84dbd92..cede8e8 100644
--- a/openbsc/tests/Makefile.am
+++ b/openbsc/tests/Makefile.am
@@ -1,4 +1,4 @@
-SUBDIRS = gsm0408 db channel mgcp gprs
+SUBDIRS = gsm0408 db channel mgcp gprs si
 
 if BUILD_NAT
 SUBDIRS += bsc-nat
diff --git a/openbsc/tests/si/Makefile.am b/openbsc/tests/si/Makefile.am
new file mode 100644
index 0000000..63cf6f8
--- /dev/null
+++ b/openbsc/tests/si/Makefile.am
@@ -0,0 +1,12 @@
+INCLUDES = $(all_includes) -I$(top_srcdir)/include
+AM_CFLAGS=-Wall -ggdb3 $(LIBOSMOCORE_CFLAGS) $(LIBOSMOSCCP_CFLAGS) $(COVERAGE_CFLAGS)
+
+EXTRA_DIST = si_test.ok
+
+noinst_PROGRAMS = si_test
+
+si_test_SOURCES = si_test.c
+
+si_test_LDADD = $(top_builddir)/src/libbsc/libbsc.a \
+		$(top_builddir)/src/libcommon/libcommon.a \
+		$(LIBOSMOCORE_LIBS) -lrt $(LIBOSMOSCCP_LIBS) $(LIBOSMOVTY_LIBS)
diff --git a/openbsc/tests/si/si_test.c b/openbsc/tests/si/si_test.c
new file mode 100644
index 0000000..16f6ea3
--- /dev/null
+++ b/openbsc/tests/si/si_test.c
@@ -0,0 +1,156 @@
+
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <openbsc/arfcn_range_encode.h>
+
+#include <osmocom/core/utils.h>
+
+#define DBG(...)
+
+#define VERIFY(res, cmp, wanted)					\
+	if (!(res cmp wanted)) {					\
+		printf("ASSERT failed: %s:%d Wanted: %d %s %d\n",	\
+			__FILE__, __LINE__, res, # cmp, wanted);	\
+	}
+
+
+static int freqs1[] = {
+	12, 70, 121, 190, 250, 320, 401, 475, 520, 574, 634, 700, 764, 830, 905, 980
+};
+
+static int freqs2[] = {
+	402, 460, 1, 67, 131, 197, 272, 347,
+};
+
+static int freqs3[] = {
+	68, 128, 198, 279, 353, 398, 452,
+
+};
+
+static int w_out[] = {
+	122, 2, 69, 204, 75, 66, 60, 70, 83, 3, 24, 67, 54, 64, 70, 9,
+};
+
+static int range128[] = {
+	1, 1 + 127,
+};
+
+static int range256[] = {
+	1, 1 + 128,
+};
+
+static int range512[] = {
+	1, 1+ 511,
+};
+
+
+static void test_arfcn_filter()
+{
+	int arfcns[50], i, res, f0_included;
+	for (i = 0; i < ARRAY_SIZE(arfcns); ++i)
+		arfcns[i] = (i + 1) * 2;
+
+	/* check that the arfcn is taken out. f0_included is only set for Range1024 */
+	f0_included = 24;
+	res = range_enc_filter_arfcns(ARFCN_RANGE_512, arfcns, ARRAY_SIZE(arfcns),
+			arfcns[0], &f0_included);
+	VERIFY(res, ==, ARRAY_SIZE(arfcns) - 1);
+	VERIFY(f0_included, ==, 0);
+	for (i = 0; i < res; ++i)
+		VERIFY(arfcns[i], ==, ((i+2) * 2) - (2+1));
+
+	/* check with range1024 */
+	for (i = 0; i < ARRAY_SIZE(arfcns); ++i)
+		arfcns[i] = (i + 1) * 2;
+	res = range_enc_filter_arfcns(ARFCN_RANGE_1024, arfcns, ARRAY_SIZE(arfcns),
+			arfcns[0], &f0_included);
+	VERIFY(res, ==, ARRAY_SIZE(arfcns) - 1);
+	VERIFY(f0_included, ==, 1);
+	for (i = 0; i < res; ++i)
+		VERIFY(arfcns[i], ==, ((i + 2) * 2) - 1);
+
+	/* check with range1024, not included */
+	for (i = 0; i < ARRAY_SIZE(arfcns); ++i)
+		arfcns[i] = (i + 1) * 2;
+	res = range_enc_filter_arfcns(ARFCN_RANGE_1024, arfcns, ARRAY_SIZE(arfcns),
+			11, &f0_included);
+	VERIFY(res, ==, ARRAY_SIZE(arfcns));
+	VERIFY(f0_included, ==, 0);
+	for (i = 0; i < res; ++i)
+		VERIFY(arfcns[i], ==, ((i + 1) * 2) - 1);
+}
+
+static void test_print_encoding()
+{
+	int rc;
+	int w[17];
+	uint8_t chan_list[16];
+	memset(chan_list, 0x23, sizeof(chan_list));
+
+	for (rc = 0; rc < ARRAY_SIZE(w); ++rc)
+		switch (rc % 3) {
+		case 0:
+			w[rc] = 0xAAAA;
+			break;
+		case 1:
+			w[rc] = 0x5555;
+			break;
+		case 2:
+			w[rc] = 0x9696;
+			break;
+		}
+
+	rc = range_enc_range512(chan_list, 0x96, w);
+	VERIFY(rc, ==, 0);
+
+	printf("Range512: %s\n", osmo_hexdump(chan_list, ARRAY_SIZE(chan_list)));
+}
+
+int main(int argc, char **argv)
+{
+	int ws[(sizeof(freqs1)/sizeof(freqs1[0]))];
+	int i, f0 = 0xFFFFFF;
+
+	memset(&ws[0], 0x23, sizeof(ws));
+
+	i = range_enc_find_index(1023, freqs1, ARRAY_SIZE(freqs1));
+	printf("Element is: %d => freqs[i] = %d\n", i, freqs1[i]);
+	VERIFY(i, ==, 2);
+
+	i = range_enc_find_index(511, freqs2, ARRAY_SIZE(freqs2));
+	printf("Element is: %d => freqs[i] = %d\n", i, freqs2[i]);
+	VERIFY(i, ==, 2);
+
+	i = range_enc_find_index(511, freqs3, ARRAY_SIZE(freqs3));
+	printf("Element is: %d => freqs[i] = %d\n", i, freqs3[i]);
+	VERIFY(i, ==, 0);
+
+	i = range_enc_arfcns(1023, freqs1, ARRAY_SIZE(freqs1), ws, 0);
+	VERIFY(i, ==, 0);
+
+	for (i = 0; i < sizeof(freqs1)/sizeof(freqs1[0]); ++i) {
+		printf("w[%d]=%d\n", i, ws[i]);
+		VERIFY(ws[i], ==, w_out[i]);
+	}
+
+	i = range_enc_determine_range(range128, ARRAY_SIZE(range128), &f0);
+	VERIFY(i, ==, ARFCN_RANGE_128);
+	VERIFY(f0, ==, 1);
+
+	i = range_enc_determine_range(range256, ARRAY_SIZE(range256), &f0);
+	VERIFY(i, ==, ARFCN_RANGE_256);
+	VERIFY(f0, ==, 1);
+
+	i = range_enc_determine_range(range512, ARRAY_SIZE(range512), &f0);
+	VERIFY(i, ==, ARFCN_RANGE_512);
+	VERIFY(f0, ==, 1);
+
+
+	test_arfcn_filter();
+	test_print_encoding();
+
+	return 0;
+}
diff --git a/openbsc/tests/si/si_test.ok b/openbsc/tests/si/si_test.ok
new file mode 100644
index 0000000..6c4b028
--- /dev/null
+++ b/openbsc/tests/si/si_test.ok
@@ -0,0 +1,20 @@
+Element is: 2 => freqs[i] = 121
+Element is: 2 => freqs[i] = 1
+Element is: 0 => freqs[i] = 68
+w[0]=122
+w[1]=2
+w[2]=69
+w[3]=204
+w[4]=75
+w[5]=66
+w[6]=60
+w[7]=70
+w[8]=83
+w[9]=3
+w[10]=24
+w[11]=67
+w[12]=54
+w[13]=64
+w[14]=70
+w[15]=9
+Range512: 88 4b 2a 95 65 95 55 2c a9 55 aa 55 6a 95 59 55 
diff --git a/openbsc/tests/testsuite.at b/openbsc/tests/testsuite.at
index 22f0b74..8e12773 100644
--- a/openbsc/tests/testsuite.at
+++ b/openbsc/tests/testsuite.at
@@ -37,3 +37,9 @@
 cat $abs_srcdir/bsc-nat/bsc_nat_test.ok > expout
 AT_CHECK([$abs_top_builddir/tests/bsc-nat/bsc_nat_test], [], [expout], [ignore])
 AT_CLEANUP
+
+AT_SETUP([si])
+AT_KEYWORDS([si])
+cat $abs_srcdir/si/si_test.ok > expout
+AT_CHECK([$abs_top_builddir/tests/si/si_test], [], [expout], [ignore])
+AT_CLEANUP