diff --git a/lib/decoding/osmocom/coding/gsm0503_interleaving.h b/lib/decoding/osmocom/coding/gsm0503_interleaving.h
new file mode 100644
index 0000000..f97dff4
--- /dev/null
+++ b/lib/decoding/osmocom/coding/gsm0503_interleaving.h
@@ -0,0 +1,51 @@
+#pragma once
+
+#include <osmocom/core/bits.h>
+
+void gsm0503_xcch_deinterleave(sbit_t *cB, const sbit_t *iB);
+void gsm0503_xcch_interleave(ubit_t *cB, ubit_t *iB);
+
+void gsm0503_tch_fr_deinterleave(sbit_t *cB, sbit_t *iB);
+void gsm0503_tch_fr_interleave(ubit_t *cB, ubit_t *iB);
+
+void gsm0503_tch_hr_deinterleave(sbit_t *cB, sbit_t *iB);
+void gsm0503_tch_hr_interleave(ubit_t *cB, ubit_t *iB);
+
+void gsm0503_mcs1_ul_deinterleave(sbit_t *hc, sbit_t *dc, const sbit_t *iB);
+void gsm0503_mcs1_ul_interleave(const ubit_t *hc,
+	const ubit_t *dc, ubit_t *iB);
+
+void gsm0503_mcs1_dl_deinterleave(sbit_t *u, sbit_t *hc,
+	sbit_t *dc, const sbit_t *iB);
+void gsm0503_mcs1_dl_interleave(const ubit_t *up, const ubit_t *hc,
+	const ubit_t *dc, ubit_t *iB);
+
+void gsm0503_mcs5_ul_deinterleave(sbit_t *hc, sbit_t *dc,
+	const sbit_t *hi, const sbit_t *di);
+void gsm0503_mcs5_ul_interleave(const ubit_t *hc, const ubit_t *dc,
+	ubit_t *hi, ubit_t *di);
+
+void gsm0503_mcs5_dl_deinterleave(sbit_t *hc, sbit_t *dc,
+	const sbit_t *hi, const sbit_t *di);
+void gsm0503_mcs5_dl_interleave(const ubit_t *hc, const ubit_t *dc,
+	ubit_t *hi, ubit_t *di);
+
+void gsm0503_mcs7_ul_deinterleave(sbit_t *hc, sbit_t *c1, sbit_t *c2,
+	const sbit_t *hi, const sbit_t *di);
+void gsm0503_mcs7_ul_interleave(const ubit_t *hc, const ubit_t *c1,
+	const ubit_t *c2, ubit_t *hi, ubit_t *di);
+
+void gsm0503_mcs7_dl_deinterleave(sbit_t *hc, sbit_t *c1, sbit_t *c2,
+	const sbit_t *hi, const sbit_t *di);
+void gsm0503_mcs7_dl_interleave(const ubit_t *hc, const ubit_t *c1,
+	const ubit_t *c2, ubit_t *hi, ubit_t *di);
+
+void gsm0503_mcs8_ul_deinterleave(sbit_t *hc, sbit_t *c1, sbit_t *c2,
+	const sbit_t *hi, const sbit_t *di);
+void gsm0503_mcs8_ul_interleave(const ubit_t *hc, const ubit_t *c1,
+	const ubit_t *c2, ubit_t *hi, ubit_t *di);
+
+void gsm0503_mcs8_dl_deinterleave(sbit_t *hc, sbit_t *c1, sbit_t *c2,
+	const sbit_t *hi, const sbit_t *di);
+void gsm0503_mcs8_dl_interleave(const ubit_t *hc, const ubit_t *c1,
+	const ubit_t *c2, ubit_t *hi, ubit_t *di);