diff --git a/gpssim.h b/gpssim.h
index c30b227..2ae0802 100644
--- a/gpssim.h
+++ b/gpssim.h
@@ -75,7 +75,7 @@
 #define SC08 (8)
 #define SC16 (16)
 
-#define EPHEM_ARRAY_SIZE (13) // for daily GPS broadcast ephemers file (brdc)
+#define EPHEM_ARRAY_SIZE (20) // for daily GPS broadcast ephemers file (brdc)
 
 /*! \brief Structure representing GPS time */
 typedef struct
