From a185b39871704e50ad9cddc39db80eae6c462f0a Mon Sep 17 00:00:00 2001
From: Bastian Bloessl <bloessl@ccs-labs.org>
Date: Tue, 14 Apr 2015 13:13:01 +0200
Subject: [PATCH] parser: don't average, let do this subsequent blocks

---
 lib/ofdm_parse_mac.cc | 26 +++++++-------------------
 1 file changed, 7 insertions(+), 19 deletions(-)

diff --git a/lib/ofdm_parse_mac.cc b/lib/ofdm_parse_mac.cc
index 4da7b12..832e829 100644
--- a/lib/ofdm_parse_mac.cc
+++ b/lib/ofdm_parse_mac.cc
@@ -23,8 +23,6 @@
 
 using namespace gr::ieee802_11;
 
-#define FER_ALPHA 0.2f
-
 class ofdm_parse_mac_impl : public ofdm_parse_mac {
 
 public:
@@ -33,15 +31,13 @@ ofdm_parse_mac_impl(bool log, bool debug) :
 		block("ofdm_parse_mac",
 				gr::io_signature::make(0, 0, 0),
 				gr::io_signature::make(0, 0, 0)),
-		d_log(log),
+		d_log(log), d_last_seq_no(0),
 		d_debug(debug) {
 
-    message_port_register_in(pmt::mp("in"));
-    set_msg_handler(pmt::mp("in"), boost::bind(&ofdm_parse_mac_impl::parse, this, _1));
+	message_port_register_in(pmt::mp("in"));
+	set_msg_handler(pmt::mp("in"), boost::bind(&ofdm_parse_mac_impl::parse, this, _1));
 
-    message_port_register_out(pmt::mp("fer"));
-    d_last_fer = 0.0f;
-    d_last_seq_no = 0;
+	message_port_register_out(pmt::mp("fer"));
 }
 
 ~ofdm_parse_mac_impl() {
@@ -270,19 +266,12 @@ void parse_data(char *buf, int length) {
 	dout << "d_last_seq_no: " << d_last_seq_no << std::endl;
 	dout << "lost frames: " << lost_frames << std::endl;
 
-	// calculate instantaneous error rate
-	float curr_fer = 0.0f;
-	if (lost_frames > 0)
-		curr_fer = 1 - (1 / (static_cast<float>(lost_frames) + 1));
-	dout << "instantaneous fer: " << curr_fer << std::endl;
-
-	// update FER estimate
-	float fer = (1.0f - FER_ALPHA) * d_last_fer + FER_ALPHA * curr_fer;
-	dout << "rolling fer: " << fer << std::endl;
+	// calculate frame error rate
+	float fer = 1 - (1 / (static_cast<float>(lost_frames) + 1));
+	dout << "instantaneous fer: " << fer << std::endl;
 
 	// keep track of values
 	d_last_seq_no = seq_no;
-	d_last_fer = fer;
 
 	// publish FER estimate
 	pmt::pmt_t pdu = pmt::make_f32vector(1, fer * 100);
@@ -370,7 +359,6 @@ void print_ascii(char* buf, int length) {
 private:
 	bool d_log;
 	bool d_debug;
-	float d_last_fer;
 	int d_last_seq_no;
 };