diff --git a/infrastructure-centred/owlps-listener/owlps-listenerd.c b/infrastructure-centred/owlps-listener/owlps-listenerd.c
index 8f4fd76..7fd5e39 100644
--- a/infrastructure-centred/owlps-listener/owlps-listenerd.c
+++ b/infrastructure-centred/owlps-listener/owlps-listenerd.c
@@ -1031,7 +1031,7 @@ void print_usage()
          "\t%s [-f config_file] [-m mode] [-d aggregation_ip]"
          " [-l listening_port] [-p aggregation_port] -r rtap_iface"
          " [-w wifi_iface] [-k] [-v | -q] [-c | -Q] [-A]"
-         " [-a autocalibration_port]"
+         " [-P autocalibration_request_port ] [-a autocalibration_port]"
          " [-H autocalibration_hello_delay] [-t autocalibration_delay]"
          " [-n autocalibration_nb_packets]\n"
          "\t%s -h\n"
@@ -1060,16 +1060,16 @@ void print_usage()
          "Autocalibration options:\n"
          "(These options are available only if the program was compiled"
          " with support of POSIX threads.)\n"
-         "\t-A\t\tEnable autocalibration (default: disabled).\n"
-         "\t-P port\t\tPort on which autocalibration positioning"
+         "\t-A\t\t\tEnable autocalibration (default: disabled).\n"
+         "\t-P autocalib_req_port\tPort on which autocalibration positioning"
          " requests are sent (default: %d).\n"
-         "\t-a port\t\tPort on which autocalibration data (hello & orders)"
+         "\t-a autocalib_port\tPort on which autocalibration data (hello & orders)"
          " are exchanged with the aggregation server (default: %d).\n"
-         "\t-H hello_delay\tTime between each hello"
+         "\t-H hello_delay\t\tTime between each hello"
          " message sent to the aggregation server (default: %d s).\n"
-         "\t-t delay\tTime between each autocalibration"
+         "\t-t delay\t\tTime between each autocalibration"
          " packet transmission (default: %d µs).\n"
-         "\t-n nb_packets\tNumber of packet transmitted"
+         "\t-n nb_packets\t\tNumber of packet transmitted"
          " for one autocalibration request (default: %d).\n"
 
          "Other options:\n"