Table 2 Distributed PDA detector with turbo BS cooperations

1) Initialize at the 0th iteration

 ∙ BS₁, set \(p(x^{1}_{k}) = 1/M\) and calculate p(x _k |y ¹) and \(\mathbf {\Lambda }^{1}_{k}\) according to Table 1 using local data y ¹.

 ∙ BS₂, set \(p(x^{2}_{k})\) based on \(\mathbf {\Lambda }^{1}_{k}\), calculate p(x _k |y ^1:2) according to Table 1 using local data y ², update \(\mathbf {\Lambda }^{2}_{k}\) by (28).

 ∙ if |p(x _k |y ¹)−p(x _k |y ^1:2)|<ε, go to 3); otherwise go to 2).

2) Iterate until APP p(x _k |y ^1:2) converges. And at the t-th iteration, perform for i=1:2

 ∙ according to Table 1, update p(x _k |y ^1:2) using data y ⁱ with prior \(p(x^{i}_{k})\) obtained from \(\mathbf {\Lambda }^{s}_{k}\), s≠i.

 ∙ update \(\mathbf {\Lambda }^{i}_{k}\) according to (30).

3) Detect x _k according to (3).