1 files changed, 95 insertions, 27 deletions
diff --git a/gr-trellis/src/python/qa_trellis.py b/gr-trellis/src/python/qa_trellis.py
index cfeefea06..b50679f27 100755
--- a/gr-trellis/src/python/qa_trellis.py
+++ b/gr-trellis/src/python/qa_trellis.py
@@ -20,46 +20,50 @@
 # Boston, MA 02110-1301, USA.
 # 
 
-from gnuradio import gr, gr_unittest
+import math
+
+
+from gnuradio import gr, gr_unittest, blks2
+# It's pretty ugly that we can't import trellis from gnuradio in this test
+# but because it runs on the non-installed python code it's all a mess.
 import trellis
 
-class test_trellis (gr_unittest.TestCase):
+import os
+import digital_swig
 
-    def setUp (self):
-        self.tb = gr.top_block ()
+fsm_args = {"awgn1o2_4": (2, 4, 4,
+                          (0, 2, 0, 2, 1, 3, 1, 3),
+                          (0, 3, 3, 0, 1, 2, 2, 1),
+                          ),
+            "rep2": (2, 1, 4, (0, 0), (0, 3)),
+            "nothing": (2, 1, 2, (0, 0), (0, 1)),
+            }
 
-    def tearDown (self):
-        self.tb = None
+constells = {2: digital_swig.constellation_bpsk(),
+             4: digital_swig.constellation_qpsk(),
+             }
+
+class test_trellis (gr_unittest.TestCase):
 
     def test_001_fsm (self):
-        I = 2
-        S = 4
-        O = 4
-        NS = (0, 2, 0, 2, 1, 3, 1, 3)
-        OS = (0, 3, 3, 0, 1, 2, 2, 1)
-        f = trellis.fsm(I,S,O,NS,OS)
-        self.assertEqual((I,S,O,NS,OS),(f.I(),f.S(),f.O(),f.NS(),f.OS()))
+        f = trellis.fsm(*fsm_args["awgn1o2_4"])
+        self.assertEqual(fsm_args["awgn1o2_4"],(f.I(),f.S(),f.O(),f.NS(),f.OS()))
 
     def test_002_fsm (self):
-        I = 2
-        S = 4
-        O = 4
-        NS = (0, 2, 0, 2, 1, 3, 1, 3)
-        OS = (0, 3, 3, 0, 1, 2, 2, 1)
-        f = trellis.fsm(I,S,O,NS,OS)
+        f = trellis.fsm(*fsm_args["awgn1o2_4"])
         g = trellis.fsm(f)
         self.assertEqual((g.I(),g.S(),g.O(),g.NS(),g.OS()),(f.I(),f.S(),f.O(),f.NS(),f.OS()))
 
     def test_003_fsm (self):
-        I = 2
-        S = 4
-        O = 4
-        NS = (0, 2, 0, 2, 1, 3, 1, 3)
-        OS = (0, 3, 3, 0, 1, 2, 2, 1)
+        # FIXME: no file "awgn1o2_4.fsm"
         #f = trellis.fsm("awgn1o2_4.fsm")
-        #self.assertEqual((I,S,O,NS,OS),(f.I(),f.S(),f.O(),f.NS(),f.OS()))
-        # temporary fix so that make distcheck does not fail on this
-        self.assertEqual(0,0)
+        #self.assertEqual(fsm_args["awgn1o2_4"],(f.I(),f.S(),f.O(),f.NS(),f.OS()))
+        pass
+
+    def test_004_fsm(self):
+        """ Test to make sure fsm works with a single state fsm."""
+        # Just checking that it initializes properly.
+        f = trellis.fsm(*fsm_args["rep2"])
 
     def test_001_interleaver (self):
         K = 5
@@ -68,5 +72,69 @@ class test_trellis (gr_unittest.TestCase):
         i = trellis.interleaver(K,IN)
         self.assertEqual((K,IN,DIN),(i.K(),i.INTER(),i.DEINTER()))
 
+    def test_001_viterbi(self):
+        """
+        Runs some coding/decoding tests with a few different FSM
+        specs.
+        """
+        for name, args in fsm_args.items():
+            constellation = constells[args[2]]
+            fsms = trellis.fsm(*args)
+            noise = 0.1
+            tb = trellis_tb(constellation, fsms, noise)
+            tb.run()
+            # Make sure all packets succesfully transmitted.
+            self.assertEqual(tb.dst.ntotal(), tb.dst.nright())
+
+
+class trellis_tb(gr.top_block):
+    """
+    A simple top block for use testing gr-trellis.
+    """
+    def __init__(self, constellation, f, N0=0.25, seed=-666L):
+        """
+        constellation - a constellation object used for modulation.
+        f - a finite state machine specification used for coding.
+        N0 - noise level
+        seed - random seed
+        """
+        super(trellis_tb, self).__init__()
+        # packet size in bits (make it multiple of 16 so it can be packed in a short)
+        packet_size = 1024*16
+        # bits per FSM input symbol
+        bitspersymbol = int(round(math.log(f.I())/math.log(2))) # bits per FSM input symbol
+        # packet size in trellis steps
+        K = packet_size/bitspersymbol
+
+        # TX
+        src = gr.lfsr_32k_source_s()
+        # packet size in shorts
+        src_head = gr.head (gr.sizeof_short, packet_size/16)
+        # unpack shorts to symbols compatible with the FSM input cardinality
+        s2fsmi = gr.packed_to_unpacked_ss(bitspersymbol, gr.GR_MSB_FIRST) 
+        # initial FSM state = 0
+        enc = trellis.encoder_ss(f, 0) 
+        mod = gr.chunks_to_symbols_sc(constellation.points(), 1)
+
+        # CHANNEL
+        add = gr.add_cc()
+        noise = gr.noise_source_c(gr.GR_GAUSSIAN,math.sqrt(N0/2),seed)
+
+        # RX
+        # data preprocessing to generate metrics for Viterbi
+        metrics = trellis.constellation_metrics_cf(constellation.base(), digital_swig.TRELLIS_EUCLIDEAN) 
+        # Put -1 if the Initial/Final states are not set.
+        va = trellis.viterbi_s(f, K, 0, -1)
+        # pack FSM input symbols to shorts
+        fsmi2s = gr.unpacked_to_packed_ss(bitspersymbol, gr.GR_MSB_FIRST) 
+        # check the output
+        self.dst = gr.check_lfsr_32k_s()
+    
+        self.connect (src, src_head, s2fsmi, enc, mod)
+        self.connect (mod, (add, 0))
+        self.connect (noise, (add, 1))
+        self.connect (add, metrics, va, fsmi2s, self.dst)
+
+
 if __name__ == '__main__':
     gr_unittest.run(test_trellis, "test_trellis.xml")