Support for conjugate downlink signals

grc/lora_receiver.xml

@@ -4,7 +4,7 @@
   <key>lora_lora_receiver</key>
   <category>[LoRa]</category>
   <import>import lora</import>
-  <make>lora.lora_receiver($in_samp_rate, $center_freq, $channel_list, $sf, $out_samp_rate, $implicit, $cr, $crc)</make>
+  <make>lora.lora_receiver($in_samp_rate, $center_freq, $channel_list, $sf, $out_samp_rate, $implicit, $cr, $crc, $conj)</make>
 
   <callback>set_center_freq($freq)</callback>
   <callback>set_sf($sf)</callback>
@@ -91,6 +91,14 @@
       </option>
   </param>
 
+  <param>
+    <name>Conjugate downlink signal</name>
+    <key>conj</key>
+    <value>False</value>
+    <type>bool</type>
+    <hide>part</hide>
+  </param>
+
   <param>
     <name>Output sample rate</name>
     <key>out_samp_rate</key>

python/lora_receiver.py

@@ -20,13 +20,14 @@
 #
 
 from gnuradio import gr
+import gnuradio
 import lora
 
 class lora_receiver(gr.hier_block2):
     """
     docstring for block lora_receiver
     """
-    def __init__(self, in_samp_rate, center_freq, channel_list, sf, out_samp_rate, implicit, cr, crc):
+    def __init__(self, in_samp_rate, center_freq, channel_list, sf, out_samp_rate, implicit, cr, crc, conj=False):
         gr.hier_block2.__init__(self,
             "lora_receiver",  # Min, Max, gr.sizeof_<type>
             gr.io_signature(1, 1, gr.sizeof_gr_complex),  # Input signature
@@ -38,8 +39,10 @@ class lora_receiver(gr.hier_block2):
         self.sf            = sf
         self.out_samp_rate = out_samp_rate
         self.channel_list  = channel_list
+        self.conj          = conj
 
         # Define blocks
+        self.block_conj = gnuradio.blocks.conjugate_cc()
         self.channelizer = lora.channelizer(in_samp_rate, out_samp_rate, center_freq, channel_list)
         self.decoder = lora.decoder(out_samp_rate, sf, implicit, cr, crc)
 
@@ -48,7 +51,11 @@ class lora_receiver(gr.hier_block2):
 
         # Connect blocks
         self.connect((self, 0), (self.channelizer, 0))
-        self.connect((self.channelizer, 0), (self.decoder, 0))
+        if self.conj:
+            self.connect((self.channelizer, 0), (self.block_conj, 0))
+            self.connect((self.block_conj, 0), (self.decoder, 0))
+        else:
+            self.connect((self.channelizer, 0), (self.decoder, 0))
         self.msg_connect((self.decoder, 'frames'), (self, 'frames'))
         self.msg_connect((self.decoder, 'control'), (self.channelizer, 'control'))