viterbi.v

这是关于智能天线的自适应算法的MATLAB代码

`timescale 1ns / 1ps
//////////////////////////////////////////////////////////////////////////////////
// Company: 
// Engineer: 
// 
// Create Date:    20:01:28 07/27/2007 
// Design Name: 
// Module Name:    viterbi 
// Project Name: 
// Target Devices: 
// Tool versions: 
// Description: 
//
// Dependencies: 
//
// Revision: 
// Revision 0.01 - File Created
// Additional Comments: 
//
//////////////////////////////////////////////////////////////////////////////////
module viterbi(clk, clk_div2, reset, x, y, c, rd, ready);
input clk;
input clk_div2;
input reset;
input x;
output y;
output c;
output rd;
output ready;

reg rd, ready;
reg [13:0] x_t, x_t1;
reg [3:0] cnt;
reg [2:0] cnt2;
reg [13:0] a_out, a_out1, a1, a2, a3, a4;
reg [3:0] c1, c2, c3, c4;
reg [6:0] c_t, c_t1, c_t2, c_t3, c_t4;

always @(posedge clk) begin
	if(!reset) begin //完成数据寄存以及时钟分频
		x_t <= 0;
		x_t1 <= 0;
		cnt <= 0;
	end
	else begin
	   if(cnt == 4'b1101)
			cnt <= 4'b0000;
		else
		   cnt <= cnt +1;
		x_t1 <= {x,x_t1[13:1]};
		if(cnt == 4'b0000) begin
			x_t <= x_t1;
		end
		else
		   x_t <= x_t;
	end	
end

always @(posedge clk_div2) begin
   if(!reset) begin
		cnt2 <= 0;
		a1 <= 0;
		a2 <= 0;
		a3 <= 0;
		a4 <= 0;  
					 
		c1 <= 0;
		c2 <= 0;
		c3 <= 0;
		c4 <= 0;	

      c_t1 <= 0;
      c_t2 <= 0;
		c_t3 <= 0;
		c_t4 <= 0;		
	end
	else begin
	   cnt2 <= cnt2 + 1;
		case(cnt2)  // 遍历各个可能的状态
			3'b000: begin
					 a1[1:0] <= 2'b00;
					 a2[1:0] <= 2'b00;
					 a3[1:0] <= 2'b11;
					 a4[1:0] <= 2'b11;  // 完成搜索序列的初始配置
					 a1[13:2] <= 0;
					 a2[13:2] <= 0;
					 a3[13:2] <= 0;
					 a4[13:2] <= 0; // 完成搜索序列寄存器的初始化
					 
					 c1 <= 0;
					 c2 <= 0;
					 c3 <= 0;
					 c4 <= 0;		// 完成汉明距标志的初始化
					 
					 c_t1[6] <= 0;
					 c_t2[6] <= 0;
					 c_t3[6] <= 1;
					 c_t4[6] <= 1;   //记录译码估值			 
			end
			
			3'b001: begin				 
					 a1[3:2] <= 2'b00;
					 a2[3:2] <= 2'b11;
					 a3[3:2] <= 2'b01;
					 a4[3:2] <= 2'b10;
	
					 c1 <= {3'b000,0^x_t[0]} + {3'b000,0^x_t[1]} + {3'b000,0^x_t[2]} 
							 + {3'b000,0^x_t[3]};				 
					 c2 <= {3'b000,0^x_t[0]} + {3'b000,0^x_t[1]} + {3'b000,1^x_t[2]}
							 + {3'b000,1^x_t[3]};	
					 c3 <= {3'b000,1^x_t[0]} + {3'b000,1^x_t[1]} + {3'b000,1^x_t[2]} 
							 + {3'b000,0^x_t[3]};	
					 c4 <= {3'b000,1^x_t[0]} + {3'b000,1^x_t[1]} + {3'b000,0^x_t[2]} 
							 + {3'b000,1^x_t[3]};
							 
					 c_t1[5] <= 0;
					 c_t2[5] <= 1;
					 c_t3[5] <= 0;
					 c_t4[5] <= 1;   //记录译码估值						 
			end
			
			3'b010: begin  
					 // S1:00  路径权值判断，剪除路径
					 if((c1+{3'b000,x_t[5]^0}+{3'b000,x_t[4]^0})>
						 (c3+{3'b000,x_t[5]^1}+{3'b000,x_t[4]^1})) begin
						c1 <= c3+{3'b000,x_t[5]^1}+{3'b000,x_t[4]^1};
						a1[3:0] <= a3[3:0];
						a1[5:4] <= 2'b11;
						c_t1[4] <= 0;
						c_t1[6:5] <= c_t3[6:5];
					 end				  
					 else begin
						c1 <= c1+{3'b000,x_t[5]^0}+{3'b000,x_t[4]^0};
						a1[3:0] <= a1[3:0];
						a1[5:4] <= 2'b00;
						c_t1[4] <= 0;
						c_t1[6:5] <= c_t1[6:5];
					 end
						
					 // S2:10 路径权值判断，剪除路径
					 if((c1+{3'b000,x_t[5]^1}+{3'b000,x_t[4]^1})>
						 (c3+{3'b000,x_t[5]^0}+{3'b000,x_t[4]^0})) begin
						c2 <= c3+{3'b000,x_t[5]^0}+{3'b000,x_t[4]^0};
						a2[3:0] <= a3[3:0];
						a2[5:4] <= 2'b00;
						c_t2[4] <=  1;
						c_t2[6:5] <= c_t3[6:5];
					 end				  
					 else begin
						c2 <= c1+{3'b000,x_t[5]^1}+{3'b000,x_t[4]^1};
						a2[3:0] <= a1[3:0];
						a2[5:4] <= 2'b11;
						c_t2[4] <=  1;
						c_t2[6:5] <= c_t1[6:5];
					 end				    
					
					 // S3:01
					 if((c2+{3'b000,x_t[5]^0}+{3'b000,x_t[4]^1})>
						 (c4+{3'b000,x_t[5]^1}+{3'b000,x_t[4]^0})) begin
						c3 <= c4+{3'b000,x_t[5]^1}+{3'b000,x_t[4]^0};
						a3[3:0] <= a4[3:0];
						a3[5:4] <= 2'b10;
						c_t3[4] <= 0;
						c_t3[6:5] <= c_t4[6:5];
					 end				  
					 else begin
						c3 <= c2+{3'b000,x_t[5]^0}+{3'b000,x_t[4]^1};
						a3[3:0] <= a2[3:0];
						a3[5:4] <= 2'b01;
						c_t3[4] <= 0;
						c_t3[6:5] <= c_t2[6:5];
					 end	
					 
					 // S4:11
					 if((c2+{3'b000,x_t[5]^1}+{3'b000,x_t[4]^0})>
						(c4+{3'b000,x_t[5]^0}+{3'b000,x_t[4]^1})) begin
						c4 <= c4+{3'b000,x_t[5]^0}+{3'b000,x_t[4]^1};
						a4[3:0] <= a4[3:0];
						a4[5:4] <= 2'b01;
						c_t4[4] <= 1;
						c_t4[6:5] <= c_t4[6:5];
					 end				  
					 else begin
						c4 <= c2+{3'b000,x_t[5]^1}+{3'b000,x_t[4]^0};
						a4[3:0] <= a2[3:0];
						a4[5:4] <= 2'b10;
						c_t4[4] <= 1;
						c_t4[6:5] <= c_t2[6:5];
					 end					 							
			end
			
			3'b011: begin
					  // S1:00
					 if((c1+{3'b000,x_t[7]^0}+{3'b000,x_t[6]^0})>
					  (c3+{3'b000,x_t[7]^1}+{3'b000,x_t[6]^1})) begin
						c1 <= c3+{3'b000,x_t[7]^1}+{3'b000,x_t[6]^1};
						a1[5:0] <= a3[5:0];
						a1[7:6] <= 2'b11;
						c_t1[3] <= 0;
						c_t1[6:4] <= c_t3[6:4];
					 end				  
					 else begin
						c1 <= c1+{3'b000,x_t[7]^0}+{3'b000,x_t[6]^0};
						a1[5:0] <= a1[5:0];
						a1[7:6] <= 2'b00;
						c_t1[3] <= 0;
						c_t1[6:4] <= c_t1[6:4];
					 end
						
					 // S2:10
					 if((c1+{3'b000,x_t[7]^1}+{3'b000,x_t[6]^1})>
					  (c3+{3'b000,x_t[7]^0}+{3'b000,x_t[6]^0})) begin
						c2 <= c3+{3'b000,x_t[7]^0}+{3'b000,x_t[6]^0};
						a2[5:0] <= a3[5:0];
						a2[7:6] <= 2'b00;
						c_t2[3] <= 1;
						c_t2[6:4] <= c_t3[6:4];
					 end				  
					 else begin
						c2 <= c1+{3'b000,x_t[7]^1}+{3'b000,x_t[6]^1};
						a2[5:0] <= a1[5:0];
						a2[7:6] <= 2'b11;
						c_t2[3] <= 1;
						c_t2[6:4] <= c_t1[6:4];
					 end				    
					
					 // S3:01
					 if((c2+{3'b000,x_t[7]^0}+{3'b000,x_t[6]^1})>
					  (c4+{3'b000,x_t[7]^1}+{3'b000,x_t[6]^0})) begin
						c3 <= c4+{3'b000,x_t[7]^1}+{3'b000,x_t[6]^0};
						a3[5:0] <= a4[5:0];
						a3[7:6] <= 2'b10;
						c_t3[3] <= 0;
						c_t3[6:4] <= c_t4[6:4];
					 end				  
					 else begin
						c3 <= c2+{3'b000,x_t[7]^0}+{3'b000,x_t[6]^1};
						a3[5:0] <= a2[5:0];
						a3[7:6] <= 2'b01;
						c_t3[3] <= 0;
						c_t3[6:4] <= c_t2[6:4];
					 end	
					 
					 // S4:11
					 if((c2+{3'b000,x_t[7]^1}+{3'b000,x_t[6]^0})>
					  (c4+{3'b000,x_t[7]^0}+{3'b000,x_t[6]^1})) begin
						c4 <= c4+{3'b000,x_t[7]^0}+{3'b000,x_t[6]^1};
						a4[5:0] <= a4[5:0];
						a4[7:6] <= 2'b01;
						c_t4[3] <= 1;
						c_t4[6:4] <= c_t4[6:4];
					 end				  
					 else begin
						c4 <= c2+{3'b000,x_t[7]^1}+{3'b000,x_t[6]^0};
						a4[5:0] <= a2[5:0];
						a4[7:6] <= 2'b10;
						c_t4[3] <= 1;
						c_t4[6:4] <= c_t2[6:4];
					 end					 	
			end
			
			3'b100: begin
					  // S1:00
					 if((c1+{3'b000,x_t[9]^0}+{3'b000,x_t[8]^0})>
					 (c3+{3'b000,x_t[9]^1}+{3'b000,x_t[8]^1})) begin
						c1 <= c3+{3'b000,x_t[9]^1}+{3'b000,x_t[8]^1};
						a1[7:0] <= a3[7:0];
						a1[9:8] <= 2'b11;
						c_t1[2] <= 0;
						c_t1[6:3] <= c_t3[6:3];
					 end				  
					 else begin
						c1 <= c1+{3'b000,x_t[9]^0}+{3'b000,x_t[8]^0};
						a1[7:0] <= a1[7:0];
						a1[9:8] <= 2'b00;
						c_t1[2] <= 0;
						c_t1[6:3] <= c_t1[6:3];
					 end
						
					 // S2:10
					 if((c1+{3'b000,x_t[9]^1}+{3'b000,x_t[8]^1})>
					 (c3+{3'b000,x_t[9]^0}+{3'b000,x_t[8]^0})) begin
						c2 <= c3+{3'b000,x_t[9]^0}+{3'b000,x_t[8]^0};
						a2[7:0] <= a3[7:0];
						a2[9:8] <= 2'b00;
						c_t2[2] <= 1;
						c_t2[6:3] <= c_t3[6:3];
					 end				  
					 else begin
						c2 <= c1+{3'b000,x_t[9]^1}+{3'b000,x_t[8]^1};
						a2[7:0] <= a1[7:0];
						a2[9:8] <= 2'b11;
						c_t2[2] <= 1;
						c_t2[6:3] <= c_t1[6:3];
					 end				    
					
					 // S3:01
					 if((c2+{3'b000, x_t[9]^0}+{3'b000, x_t[8]^1})>
					 (c4+{3'b000,x_t[9]^1}+{3'b000,x_t[8]^0})) begin
						c3 <= c4+{3'b000,x_t[9]^1}+{3'b000,x_t[8]^0};
						a3[7:0] <= a4[7:0];
						a3[9:8] <= 2'b10;
						c_t3[2] <= 0;
						c_t3[6:3] <= c_t4[6:3];
					 end				  
					 else begin
						c3 <= c2+{3'b000, x_t[9]^0}+{3'b000, x_t[8]^1};
						a3[7:0] <= a2[7:0];
						a3[9:8] <= 2'b01;
						c_t3[2] <= 0;
						c_t3[6:3] <= c_t2[6:3];
					 end	
					 
					 // S4:11
					 if((c2+{3'b000,x_t[9]^1}+{3'b000,x_t[8]^0})>
					 (c4+{3'b000,x_t[9]}^0+{3'b000,x_t[8]^1})) begin
						c4 <= c4+{3'b000,x_t[9]}^0+{3'b000,x_t[8]^1};
						a4[7:0] <= a4[7:0];
						a4[9:8] <= 2'b01;
						c_t4[2] <= 1;
						c_t4[6:3] <= c_t4[6:3];
					 end				  
					 else begin
						c4 <= c2+{3'b000,x_t[9]^1}+{3'b000,x_t[8]^0};
						a4[7:0] <= a2[7:0];
						a4[9:8] <= 2'b10;
						c_t4[2] <= 1;
						c_t4[6:3] <= c_t2[6:3];
					 end					 	
			end
			
			3'b101: begin
					  // S1:00
					 if((c1+{3'b000,x_t[11]^0}+{3'b000,x_t[10]^0})>
					  (c3+{3'b000,x_t[11]^1}+{3'b000,x_t[10]^1})) begin
						c1 <= c3+{3'b000,x_t[11]^1}+{3'b000,x_t[10]^1};
						a1[9:0] <= a3[9:0];
						a1[11:10] <= 2'b11;
						c_t1[1] <= 0;
						c_t1[6:2] <= c_t3[6:2];
					 end				  
					 else begin
						c1 <= c1+{3'b000,x_t[11]^0}+{3'b000,x_t[10]^0};
						a1[9:0] <= a1[9:0];
						a1[11:10] <= 2'b00;
						c_t1[1] <= 0;
						c_t1[6:2] <= c_t1[6:2];
					 end
										 
					 // S3:01
					 if((c2+{3'b000,x_t[11]^1}+{3'b000,x_t[10]^0})>
					 (c4+{3'b000,x_t[11]^0}+{3'b000,x_t[10]^1})) begin
						c3 <= c4+{3'b000,x_t[11]^0}+{3'b000,x_t[10]^1};
						a3[9:0] <= a4[9:0];
						a3[11:10] <= 2'b10;
						c_t2 <= 0;
						c_t2[6:2] <= c_t4[6:2];
					 end				  
					 else begin
						c3 <= c2+{3'b000,x_t[11]^1}+{3'b000,x_t[10]^0};
						a3[9:0] <= a2[9:0];
						a3[11:10] <= 2'b01;
						c_t2 <= 0;
						c_t2[6:2] <= c_t2[6:2];
					 end					 	
			end
			
			3'b110: begin
					  // S1:00
					 if((c1+{3'b000,x_t[13]^0}+{3'b000,x_t[12]^0})>
					 (c3+{3'b000,x_t[13]^1}+{3'b000,x_t[12]^1})) begin
						c1 <= c3+{3'b000,x_t[13]^1}+{3'b000,x_t[12]^1};
						a1[11:0] <= a3[11:0];
						a1[13:12] <= 2'b11;
						a_out[11:0] <= a3[11:0];
						a_out[13:12] <= 2'b11;
						c_t1[0] <= 0;
						c_t1[6:1] <= c_t2[6:1];					
					 end	
                else begin					 
						c1 <= c1+{3'b000,x_t[13]^0}+{3'b000,x_t[12]^0};
						a1[11:0] <= a1[11:0];
						a1[13:12] <= 2'b00;
						a_out[11:0] <= a1[11:0];
						a_out[13:12] <= 2'b00;
						c_t1[0] <= 0;
						c_t1[6:1] <= c_t1[6:1];	
					 end							    
			end
			
		  default: begin		 
					 a1[1:0] <= 2'b00;
					 a2[1:0] <= 2'b00;
					 a3[1:0] <= 2'b11;
					 a4[1:0] <= 2'b11; 
					 
					 c1 <= 0;
					 c2 <= 0;
					 c3 <= 0;
					 c4 <= 0;
					 
					 c_t1 <= 0;
					 c_t2 <= 0;
					 c_t3 <= 0;
					 c_t4 <= 0;
		  end
		endcase
	end
end

always @(posedge clk) begin
   if(!reset) begin
	  ready <= 0;
	  a_out1 <= 0;
	  c_t <= 0;
	  rd <= 0;
	end
   else begin 
     if(cnt==0)
       rd <= 1;
     else
       rd <= 0;	  
	  if(cnt == 1) begin
	     c_t <= c_t1;
		  a_out1 <= a_out;
		  ready <= 1;
	  end
	  else begin
	     ready <= 0;
		  a_out1[13:0] <= {a_out1[0], a_out1[13:1]};	
		  if(cnt[0]==1)
		    c_t[6:0] <={c_t[5:0], c_t[6]};
		    
     end		  
	end
end

assign y = a_out1[0];
assign c = c_t[6];

endmodule