METHOD AND APPARATUS FOR MEASURING NONLINEAR EFFECTS IN A COMMUNICATION SYSTEM AND FOR SELECTING CHANNELS ON THE BASIS OF THE RESULTS

摘要

A method and appararatus for accurately determining the operating characteristics or im-pact of nonlinear effects on de-vices or communication systems transferring orthogonally coded spread-spectrum communication signals. A Walsh Power Ratio, is used to more accurately deter-mine system response. This in-formation can be used by power control loops in controlling or adjusting the operation of non--linear elements or stages such as high power amplifiers in orthog-onal CDMA communication sys-tems to provide improved system response. The information can also be employed in assigning channels to systems users, and to proceed with physical changes to system hardware. The mea-surements used to formulate the WPR can be made to individual components or to entire systems by injecting communication sig-nals in multiple channels containing data, and leaving at least one empt y channel. The received power per channel on the output side of the system or device is then measured. A ratio of power density for the empt y to the active channels is then formed. The determination of WPR for a system or components can be realized during periods of operatio n through periodic transfer of test signals either at allocated times or by interleaving among existing traffic signals in the system.