gr-gmr1: Make rach_detect_fft use sample_rate instead of fft_size as param

The is really no reason to use any other fft size than the auto computed
one and having the sample_rate will allow the output frequency to be
in hz rather than radian.

Signed-off-by: Sylvain Munaut <tnt@246tNt.com>

5 files changed, 31 insertions, 19 deletions

diff --git a/gr-gmr1/apps/gmr_rach_scan.grc b/gr-gmr1/apps/gmr_rach_scan.grc
index eacc799..f5a3a44 100644
--- a/gr-gmr1/apps/gmr_rach_scan.grc
+++ b/gr-gmr1/apps/gmr_rach_scan.grc
@@ -283,8 +283,8 @@
       <value>True</value>
     </param>
     <param>
-      <key>fft_size</key>
-      <value>1 &lt;&lt; int(round(math.log(samp_rate / 1e3) / math.log(2)))</value>
+      <key>samp_rate</key>
+      <value>samp_rate</value>
     </param>
     <param>
       <key>overlap_ratio</key>
diff --git a/gr-gmr1/grc/rach_detect_fft.xml b/gr-gmr1/grc/rach_detect_fft.xml
index 406db06..1bc6f81 100644
--- a/gr-gmr1/grc/rach_detect_fft.xml
+++ b/gr-gmr1/grc/rach_detect_fft.xml
@@ -5,12 +5,12 @@
  <category>GMR-1</category>
  <import>import math</import>
  <import>from gnuradio import gmr1</import>
- <make>gmr1.rach_detect_fft($fft_size, $overlap_ratio, $threshold, $burst_length, $burst_offset, $freq_offset, $len_tag_key)</make>
+ <make>gmr1.rach_detect_fft($samp_rate, $overlap_ratio, $threshold, $burst_length, $burst_offset, $freq_offset, $len_tag_key)</make>
  <param>
-   <name>FFT size</name>
-   <key>fft_size</key>
-   <value>1 &lt;&lt; int(round(math.log(samp_rate / 1e3) / math.log(2)))</value>
-   <type>int</type>
+   <name>Sample Rate</name>
+   <key>samp_rate</key>
+   <value>samp_rate</value>
+   <type>real</type>
  </param>
  <param>
    <name>Overlap ratio</name>
diff --git a/gr-gmr1/include/gnuradio/gmr1/rach_detect_fft.h b/gr-gmr1/include/gnuradio/gmr1/rach_detect_fft.h
index fbe3441..33c6f67 100644
--- a/gr-gmr1/include/gnuradio/gmr1/rach_detect_fft.h
+++ b/gr-gmr1/include/gnuradio/gmr1/rach_detect_fft.h
@@ -37,8 +37,10 @@ namespace gr {
      public:
       typedef boost::shared_ptr<rach_detect_fft> sptr;
 
-      static sptr make(int fft_size, int overlap_ratio, float threshold,
-                       int burst_length, int burst_offset, float freq_offset,
+      static sptr make(const double sample_rate,
+                       const int overlap_ratio, const float threshold,
+                       const int burst_length, const int burst_offset,
+                       const float freq_offset,
                        const std::string& len_tag_key);
     };
 
diff --git a/gr-gmr1/lib/rach_detect_fft_impl.cc b/gr-gmr1/lib/rach_detect_fft_impl.cc
index b1552be..5e39b89 100644
--- a/gr-gmr1/lib/rach_detect_fft_impl.cc
+++ b/gr-gmr1/lib/rach_detect_fft_impl.cc
@@ -43,33 +43,40 @@ static const pmt::pmt_t TIME_KEY = pmt::string_to_symbol("time");
 
 rach_detect_fft::sptr
 rach_detect_fft::make(
-	int fft_size, int overlap_ratio, float threshold,
-	int burst_length, int burst_offset, float freq_offset,
+	const double sample_rate,
+	const int overlap_ratio, const float threshold,
+	const int burst_length, const int burst_offset,
+	const float freq_offset,
 	const std::string& len_tag_key)
 {
 	return gnuradio::get_initial_sptr(
 		new rach_detect_fft_impl(
-			fft_size, overlap_ratio, threshold,
-			burst_length, burst_offset, freq_offset,
+			sample_rate,
+			overlap_ratio, threshold,
+			burst_length, burst_offset,
+			freq_offset,
 			len_tag_key
 		)
 	);
 }
 
 rach_detect_fft_impl::rach_detect_fft_impl(
-	int fft_size, int overlap_ratio, float threshold,
-	int burst_length, int burst_offset, float freq_offset,
+	const double sample_rate,
+	const int overlap_ratio, const float threshold,
+	const int burst_length, const int burst_offset,
+	const float freq_offset,
 	const std::string& len_tag_key)
     : gr::block("rach_detect_fft",
                 io_signature::make(1, 1, sizeof(gr_complex)),
                 io_signature::make(1, 1, sizeof(gr_complex))),
-      d_fft_size(fft_size), d_overlap_ratio(overlap_ratio),
-      d_threshold(threshold),
+      d_sample_rate(sample_rate),
+      d_overlap_ratio(overlap_ratio), d_threshold(threshold),
       d_burst_length(burst_length), d_burst_offset(burst_offset),
       d_freq_offset(freq_offset),
       d_len_tag_key(pmt::string_to_symbol(len_tag_key)),
       d_burst_length_pmt(pmt::from_long(burst_length))
 {
+	this->d_fft_size = 1 << (int)(round(log2(sample_rate / 1e3)));
 	this->d_fft = new gr::fft::fft_complex(this->d_fft_size, true, 1);
 
 	this->d_buf = (gr_complex *) volk_malloc(this->d_fft_size * sizeof(gr_complex), 128);
diff --git a/gr-gmr1/lib/rach_detect_fft_impl.h b/gr-gmr1/lib/rach_detect_fft_impl.h
index 0efcf0c..779d756 100644
--- a/gr-gmr1/lib/rach_detect_fft_impl.h
+++ b/gr-gmr1/lib/rach_detect_fft_impl.h
@@ -52,6 +52,7 @@ namespace gr {
         float bin() const;
       };
 
+      double d_sample_rate;
       int d_fft_size;
       int d_overlap_ratio;
       float d_threshold;
@@ -79,8 +80,10 @@ namespace gr {
       void peak_detect(uint64_t position);
 
      public:
-      rach_detect_fft_impl(int fft_size, int overlap_ratio, float threshold,
-                           int burst_length, int burst_offset, float freq_offset,
+      rach_detect_fft_impl(const double sample_rate,
+                           const int overlap_ratio, const float threshold,
+                           const int burst_length, const int burst_offset,
+                           const float freq_offset,
                            const std::string& len_tag_key);
       virtual ~rach_detect_fft_impl();