Added routine for optfir equiripple filter design code to create complex bandpass...

diff --git a/gnuradio-core/src/python/gnuradio/optfir.py b/gnuradio-core/src/python/gnuradio/optfir.py
index 06a0eea61462cfae177b7cce1b5ba9ffed2e0cca..ad5743287eefc54e3affec99c6b1fa21604c76a3 100644 (file)
--- a/gnuradio-core/src/python/gnuradio/optfir.py
+++ b/gnuradio-core/src/python/gnuradio/optfir.py
@@ -27,7 +27,7 @@ For a great intro to how all this stuff works, see section 6.6 of
 and Barrie W. Jervis, Adison-Wesley, 1993.  ISBN 0-201-54413-X.
 '''
 
-import math
+import math, cmath
 from gnuradio import gr
 
 remez = gr.remez
@@ -75,6 +75,29 @@ def band_pass (gain, Fs, freq_sb1, freq_pb1, freq_pb2, freq_sb2,
     taps = gr.remez (n + nextra_taps, fo, ao, w, "bandpass")
     return taps
 
+
+##  Builds a band pass filter with complex taps by making an LPF and
+#   spinning it up to the right center frequency
+#   @param gain  Filter gain in the passband (linear)
+#   @param Fs    Sampling rate (sps)
+#   @param freq1 End of stop band (in Hz)
+#   @param freq2 Start of pass band (in Hz)
+#   @param passband_ripple_db Pass band ripple in dB (should be small, < 1)
+#   @param stopband_atten_db  Stop band attenuation in dB (should be large, >= 60)
+#   @param nextra_taps  Extra taps to use in the filter (default=2)
+def complex_band_pass (gain, Fs, freq_sb1, freq_pb1, freq_pb2, freq_sb2,
+                       passband_ripple_db, stopband_atten_db,
+                       nextra_taps=2):
+    center_freq = (freq_pb2 + freq_pb1) / 2.0
+    lp_pb = (freq_pb2 - center_freq)/1.0
+    lp_sb = freq_sb2 - center_freq
+    lptaps = low_pass(gain, Fs, lp_pb, lp_sb, passband_ripple_db,
+                      stopband_atten_db, nextra_taps)
+    spinner = [cmath.exp(2j*cmath.pi*center_freq/Fs*i) for i in xrange(len(lptaps))]
+    taps = [s*t for s,t in zip(spinner, lptaps)]
+    return taps
+
+
 ##  Builds a high pass filter.
 #   @param gain  Filter gain in the passband (linear)
 #   @param Fs    Sampling rate (sps)

diff --git a/gr-utils/src/python/gr_filter_design.py b/gr-utils/src/python/gr_filter_design.py
index 0579d0fe2313d4e792e5c32b4ca8362ee3974c5b..4aa59360f5b3acef62372b13d83d4b1f7f94e246 100755 (executable)
--- a/gr-utils/src/python/gr_filter_design.py
+++ b/gr-utils/src/python/gr_filter_design.py
@@ -15,8 +15,6 @@ from gnuradio import gr, blks2, eng_notation
 from scipy import fftpack
 
 from pyqt_filter import Ui_MainWindow
-from pyqt_filter_firlpf import Ui_firlpfForm
-from pyqt_filter_firhpf import Ui_firhpfForm
 
 class gr_plot_filter(QtGui.QMainWindow):
     def __init__(self, qapp, options):
@@ -196,7 +194,8 @@ class gr_plot_filter(QtGui.QMainWindow):
             if(winstr == "Equiripple"):
                 designer = {"Low Pass" : self.design_opt_lpf,
                             "Band Pass" : self.design_opt_bpf,
-                            "High Pass" :  self.design_opt_hpf}        
+                            "Complex Band Pass" : self.design_opt_cbpf,
+                            "High Pass" :  self.design_opt_hpf}
                 taps,r = designer[ftype](fs, gain)
 
             else:
@@ -381,6 +380,28 @@ class gr_plot_filter(QtGui.QMainWindow):
         else:
             return ([],r)
 
+    def design_opt_cbpf(self, fs, gain, wintype=None):
+        ret = True
+        pb1,r = self.gui.startofBpfPassBandEdit.text().toDouble()
+        ret = r and ret
+        pb2,r = self.gui.endofBpfPassBandEdit.text().toDouble()
+        ret = r and ret
+        tb,r  = self.gui.bpfTransitionEdit.text().toDouble()
+        ret = r and ret
+        atten,r = self.gui.bpfStopBandAttenEdit.text().toDouble()
+        ret = r and ret
+        ripple,r = self.gui.bpfPassBandRippleEdit.text().toDouble()
+        ret = r and ret
+
+        if(r):
+            sb1 = pb1 - tb
+            sb2 = pb2 + tb
+            taps = blks2.optfir.complex_band_pass(gain, fs, sb1, pb1, pb2, sb2,
+                                                  ripple, atten)
+            return (taps,r)
+        else:
+            return ([],r)
+
     def design_opt_hpf(self, fs, gain, wintype=None):
         ret = True
         sb,r = self.gui.endofHpfStopBandEdit.text().toDouble()