說明 
135 p 
附註 
Source: Dissertation Abstracts International, Volume: 6409, Section: B, page: 4530 

Adviser: Stephen P. Boyd 

Thesis (Ph.D.)Stanford University, 2003 

In this dissertation, we describe a GPS antenna array and signalprocessing algorithms for mitigating interference and multipath based on angleofarrival differences 

We introduce an extension of minimumvariance beamforming that specifically takes into account uncertainty in the assumed array response. Sources of this uncertainty include imprecise knowledge of the angle of arrival and uncertainty in the array manifold. In our method, uncertainty in the array manifold is modeled explicitly via an uncertainty ellipsoid that gives the possible values of the array for a particular look direction. We choose weights that minimize the total weighted power output of the array, subject to the constraint that the gain exceeds unity for all array responses in this uncertainty ellipsoid. Hence, we can guarantee performance of the robust method in the presence of uncertainties. The robust weights can be computed very efficiently using Lagrange multiplier techniques 

These methods are directly applicable to antenna arrays with closely spaced elements in which the coupling between elements is significant. They extend naturally to the case where the aggregate uncertainty arises from more than one component in the signal path, e.g., the array manifold, the radio frequency (RF) electronics, etc. Measurements taken from a vertically stacked turnstile array are presented 

Application of the aforementioned methods in an array antenna system for GPS yielded substantial rejection of multipath. The usual tradeoff between antenna size and multipath performance does not apply 

School code: 0212 

DDC 
Host Item 
Dissertation Abstracts International 6409B

主題 
Engineering, Electronics and Electrical


0544

Alt Author 
Stanford University

