Updating the arb. resampler to use the optfir filter that provides better specificati...

[debian/gnuradio] / gnuradio-core / src / python / gnuradio / blks2impl / pfb_arb_resampler.py

diff --git a/gnuradio-core/src/python/gnuradio/blks2impl/pfb_arb_resampler.py b/gnuradio-core/src/python/gnuradio/blks2impl/pfb_arb_resampler.py
index b1b3dfcab57d5bbc5650e6b78c54f0299faa2f77..c4e496c45acbf2c2d9ada86df0a9fefde67e13fe 100644 (file)
--- a/gnuradio-core/src/python/gnuradio/blks2impl/pfb_arb_resampler.py
+++ b/gnuradio-core/src/python/gnuradio/blks2impl/pfb_arb_resampler.py
@@ -20,31 +20,47 @@
 # Boston, MA 02110-1301, USA.
 # 
 
-from gnuradio import gr
+from gnuradio import gr, optfir
 
 class pfb_arb_resampler_ccf(gr.hier_block2):
     '''
-    Convinience wrapper for the polyphase filterbank arbitrary resampler.
+    Convenience wrapper for the polyphase filterbank arbitrary resampler.
 
     The block takes a single complex stream in and outputs a single complex
     stream out. As such, it requires no extra glue to handle the input/output
     streams. This block is provided to be consistent with the interface to the
     other PFB block.
     '''
-    def __init__(self, rate, taps, flt_size=32):
+    def __init__(self, rate, taps=None, flt_size=32, atten=100):
        gr.hier_block2.__init__(self, "pfb_arb_resampler_ccf",
                                gr.io_signature(1, 1, gr.sizeof_gr_complex), # Input signature
                                gr.io_signature(1, 1, gr.sizeof_gr_complex)) # Output signature
         
         self._rate = rate
-        self._taps = taps
         self._size = flt_size
 
+        if taps is not None:
+            self._taps = taps
+        else:
+            # Create a filter that covers the full bandwidth of the input signal
+            bw = 0.4
+            tb = 0.2
+            ripple = 0.1
+            #self._taps = gr.firdes.low_pass_2(self._size, self._size, bw, tb, atten)
+            made = False
+            while not made:
+                try:
+                    self._taps = optfir.low_pass(self._size, self._size, bw, bw+tb, ripple, atten)
+                    made = True
+                except RuntimeError:
+                    ripple += 0.01
+                    made = False
+                    print("Warning: set ripple to %.4f dB. If this is a problem, adjust the attenuation or create your own filter taps." % (ripple))
+
         self.pfb = gr.pfb_arb_resampler_ccf(self._rate, self._taps, self._size)
 
         self.connect(self, self.pfb)
         self.connect(self.pfb, self)
         
-        
-        
-        
+    def set_taps(self, taps):
+        self.pfb.set_taps(taps)