LTE-Advanced Carrier Aggregation and Rx Sensitivity : Mechanisms and Link Budget Calculation of DeSense

LTE-Advanced was introduced in release 10 of the 3GPP spec for LTE in order to get closer to the aggressive cellular data rate targets of the strict 4G technology definition of the ITU, namely 1GB/s data rates for the downlink. This presentation will introduce this carrier aggregation feature of LTE-Advanced and the specifics of interband CA vs. contiguous vs. non-contiguous intraband CA, 3CA Downlink, and uplink contiguous intraband and interband UL CA. Implications for the radio architecture and performance challenges of CA, as well as the test and validation conformance requirements will be detailed.

One of the most critical of these performance metrics is Rx Sensitivity, as a measure of the radio minimum detectable signal. This important ability of the receiver to overcome the limitations of noise and coexistence is a challenge in today's modern smartphones with all the simultaneous radio and interference activity, and we will summarize all of the key factors that limit the reference sensitivity when the transmitter is OFF, and the additional mechanisms when the transmitter is operated at or near maximum power that degrade that reference sensitivity "“ all broken down by noise, nonlinear translation, and direct interference mechanisms "“ the so-called "DeSense". The mathematical and link budget details behind these mechanisms will be detailed, as well as intuitive explanations of the challenges to the front-end architecture and PA/filter block parameters that limit our best-in-class performance.

David Pehlke received his Ph.D. and M.S.E. from the University of Michigan and S.B.E.E from M.I.T. and is director of the Systems Engineering team for the Advanced Mobile Solutions division of Skyworks in Newbury Park. He serves as patent liaison for the AMS division, and has 31 patents issued with more pending. He is an IEEE Senior member and presently chairs the IEEE Buenaventura Communications Society.