 As such, the technique of formula_1-relaxation is sometimes employed to circumvent the difficulties of signal reconstruction using the formula_3-norm.In formula_1-relaxation, the formula_1 problem,

formula_11 subject to formula_5,

is solved in place of the formula_3 problem.Note that this relaxation is convex and hence amenable to the standard techniques of linear programming - a computationally desirable feature.