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In this paper a systematic approach to radome design is presented. The problem is formulated as a global optimization procedure such that the radome performance is optimized by properly adjusting the thickness of the radome layer over the entire radome surface. In this approach the thickness profile is parameterized via B-splines representation. Simulated annealing technique is applied to finding the best thickness profile so that the maximum boresight error is reduced as small as possible over the entire range of the antenna look angle. A two-dimensional design example is given. The best possible thickness profile is found and the boresight error is reduced considerably compared to that due to a uniform layer. The method is general and can be applied without difficulty to other realistic three-dimensional radomes of arbitrary shapes.

Because of physical constraints, the optimum control of industrial robots is a difficult problem. An alternative approach is to divide the problem into two parts: optimum pat,h planning for off-line processing followed by on-line path tracking. The path tracking can be achieved by adopting the existing approach. The path planning is done at the joint level. Cubic spline functions are used for constructing joint trajectories for mechanical manipulators. The motion of the manipulator is specified by a sequence of Cartesian knots, i.e. positions and orientations of the hand. For a &joint manipulator, these Cartesian knots are transformed into six sets of joint values, with each set corresponding to a joint. Piecewise cubic polynomials are used to fit the sequence of joint values for each of the six joints. The problem is proved to be uniquely solvable. Furthermore, an algorithm is developed to schedule the time periods between each pair of adjacent knots such that the total traveling time is minimized subject to the physical constraints on joint velocities, accelerations, and jerks. FORTRAh' programs have been written to implement (1) the procedure for constructing the cubic polynomial joint trajectories and (2) the algorithm for minimizing the traveling time. Results are given as an illustration.

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Indexing terms: Neural networks, Radio direction-finding Experimental results: Microstrip couplers reported in [I-31 are particular cases of eqn. 1. Two cases of uniplanar couplers are impor