Patent ID: 7142609

Claim:
A method for detecting and quantifying impairments of a received communication signal of a quadrature amplitude modulation (OAM) data communication system represented by a plurality of ideal values, said method comprising the steps of: a) storing a statistically significant number of a plurality of received points of said signal for each of said ideal values corresponding to a plurality of groups of said plurality of ideal values, wherein said plurality of ideal values being distributed around an origin of said coordinate system in a plurality of adjacent rows and columns forming a square shape pattern, said rows and columns being in a direction of said in-phase axis and said quadrature axis respectively, said pattern defining four outer corner ideal values, external horizontal and vertical ideal values of said two outermost of said rows and two outermost of said columns respectively, internal ideal values in a center proximity of said origin, different combinations of said received points corresponding to respective of said defined ideal values forming said plurality of groups, each of said received points being defined by an in-phase and a qadrature components in a coordinate system in which a first axis is an in-phase axis and a second axis is a quadruture axis, said components having corresponding ideal components from their respective of said ideal values, each of said groups corresponding to a respective of said imparments and being specific to the same wherein said impairments are selected from a group including signal compression ratio. I/O gain imbalance ratio, I/O phase imbalance, phase noise, signal to noise ratio, signal to interference ratio and clipping level; b) analyzing said components of said received points of respective of said groups in relation with their respective of said ideal components of said ideal values to quantify said impairments of said signal and provide calculated values of the same; c) displaying said calculated values of said impairments.