Improved quantum (t,n) threshold group signature


 Threshold signature is an important branch of digital signature, which can distribute signature rights and avoid the abuse of signature rights. With the continuous development of quantum computation and quantum information, quantum threshold signatures are gradually appearing in the limelight. Recently, a quantum (t,n) threshold group signature scheme has been analyzed, which uses techniques such as quantum-controlled-not operation and quantum teleportation. However, this scheme cannot resist forgery attack and does not conform to the design of threshold signature in the signing phase. Based on the original scheme, we propose a improved quantum (t,n) threshold signature scheme using quantum (t,n) threshold secret sharing technology. The analysis proves that the improved scheme can resist forgery attack, collusion attack, and it is undeniable. At the same time, this scheme reduces the level of trust in the arbitrator during the signature phase.