[Commit-gnuradio] r7799 - gnuradio/branches/developers/jcorgan/iqb/usrp/fpga/sdr_lib

[jcorgan]

Author: jcorgan
Date: 2008-02-23 13:40:03 -0700 (Sat, 23 Feb 2008)
New Revision: 7799

Modified:
   gnuradio/branches/developers/jcorgan/iqb/usrp/fpga/sdr_lib/iq_balancer.v
Log:
Added magnitude and phase adjustment.  Surprisingly, non-registered, 
combinatorial multipliers synthesized to a total of 67% (vs. 58%), and met slow 
timing requirements.  Untested.

Modified: 
gnuradio/branches/developers/jcorgan/iqb/usrp/fpga/sdr_lib/iq_balancer.v
===================================================================
--- gnuradio/branches/developers/jcorgan/iqb/usrp/fpga/sdr_lib/iq_balancer.v    
2008-02-23 19:54:22 UTC (rev 7798)
+++ gnuradio/branches/developers/jcorgan/iqb/usrp/fpga/sdr_lib/iq_balancer.v    
2008-02-23 20:40:03 UTC (rev 7799)
@@ -36,11 +36,11 @@
    localparam MAG_ADDR    = REGBASE + 1;
    localparam PHASE_ADDR  = REGBASE + 2;
 
-   wire [15:0] i_offset_adj;
-   wire [15:0] q_offset_adj;
-   wire [15:0] i_mag_adj;
-   wire [15:0] i_phase_adj;
-   wire [15:0] q_phase_adj;
+   wire signed [15:0] i_offset_adj;
+   wire signed [15:0] q_offset_adj;
+   wire signed [15:0] i_mag_adj;
+   wire signed [15:0] i_phase_adj;
+   wire signed [15:0] q_phase_adj;
    
    setting_reg #(OFFSET_ADDR) sr_offset
      (.clock(clock),
@@ -67,10 +67,15 @@
       .out({i_phase_adj,q_phase_adj}) );
 
    // Add in DC offset balance
-   wire [15:0] i_offset_bal = i_in + i_offset_adj;
-   wire [15:0] q_offset_bal = q_in + q_offset_adj;
+   wire signed [15:0] i_offset_bal = i_in + i_offset_adj;
+   wire signed [15:0] q_offset_bal = q_in + q_offset_adj;
    
-   assign i_out = i_offset_bal;
-   assign q_out = q_offset_bal;
+   // Apply magnitude adjustment to I channel
+   wire signed [31:0] i_mag = i_offset_bal*i_mag_adj;
+   assign i_out = i_mag[29:14];
+   
+   // Apply phase adjustment to Q channel
+   wire signed [31:0] q_phase = i_out*i_phase_adj + q_offset_bal*q_phase_adj;
+   assign q_out = q_phase[31:16];
 
 endmodule // iq_balancer