From: Distributed coalitional game for friendly jammer selection in ultra-dense networks
Initialization |
The coalitional structure is initialized as \(\Pi _{0}=\Omega =\mathbb {M}\cup \mathbb {K}\) and each player i’s history set h(i) is set empty. |
Phase 1 : Qualification Confirmation |
a Each SBS k measures the channel gain to the eavesdropper and MUEs, i.e., \(h_{k,e}^{n_{m}}\), \(h_{k,m}^{n_{m}}\), \(m\in \mathbb {M}\). |
b MBS broadcasts the collected channel information to MUEs. |
c Each player i calculates its potential partner list. For SBS k, \({\Psi _{k}} = \{ m|h_{k,e}^{{n_{m}}} / h_{k,m}^{{n_{m}}} > 1,m \in \mathbb {M}\}\), For MUE m, \({\Psi _{m}} = \{ k|h_{k,e}^{{n_{m}}} / h_{k,m}^{{n_{m}}} > 1,k \in \mathbb {K}\}\). |
Phase 2 : Coalition Formation |
Loop: |
Given the current partition Π current (in the beginning, Π current =Π 0), for every player i in coalition S∈Π current |
a Update the utility in S, U current =u k (Π current ,S) |
b For SBS, find the coalitions that contain the MUEs in Ψ i , S Ψ ={S ′|S ′∈Π current ∖S,m∈Ψ i ,m∈S ′} For MUE, find the SBSs who are still alone in Ψ i , S Ψ ={S ′|k∈Ψ i ,k∈S ′,|S ′|=1} |
c Investigate the possible switching operation among S ′∪{∅}, according to the switching rule. Record the maximal utility U max and the corresponding coalition |
d If U max >U current |
Player i stores the current coalition S into history set h(i), and joins the new coalitionelse Player i stays in the current coalition and the coalition partition does not changeend |
Until: No player deviate from its coalition. |
Phase 3 : Friendly Jamming |
The SBS in non-singleton coalition allocates α of the total power on its client MUE m’s subchannel n m to transmit the information as the jamming noise. MUE pays to its jammers according to (14) and (15). |