Abstract: A heat sink adapted to dissipate heat from an electronic component wherein a plurality of heat dissipating perforated fins project generally outwardly from a planar base and are spaced apart by channels therebetween. The height of the perforated fins to the width of the channels is at least about 8 to 1. The perforations through the fins are such that the flow of cooling fluid through the fins generally emulates the flow through a comparable pin grid array heat sink. The fin structure is such that the fin is structurally supported against deformation, particularly during cross-cutting operations.

Abstract: A method and apparatus for adaptive, variable bandwidth, high-speed data transmission of a multicarrier signal over digital subscriber lines wherein the initial optimal transmission bandwidth is identified based on initial signal-to-noise ratio (SNR) estimates of the orthogonal carriers of the multicarrier system. Maximum data throughput, or system performance margin, is achieved by assigning the total amount of information, or number of bits, to be transmitted in each multicarrier symbol to particular carriers through an initial bit allocation procedure, which is possibly subject to variable target bit error rates among the carriers. A transmit power mask, of any shape and level, is imposed upon the system by an initial energy allocation procedure that limits the maximum amount of power to be transmitted in each of the several carriers.

Abstract: Allocations of bits per transmission symbol to subchannels in a transmission system using multicarrier modulation are updated in response to requests from a receiver to a transmitter of the system, each request identifying a carrier whose bit allocation can be increased and a carrier whose bit allocation can be decreased, so that the total number of bits per symbol can be increased, decreased, or be unchanged. In order to synchronize bit allocation changes, a transmitted symbol counter at the transmitter and a received symbol counter at the receiver maintain synchronized symbol counts. In response to a request for a change in bit allocations, the transmitter sends a future symbol count value to the receiver, and the transmitter and the receiver implement the change when their respective counters match this count value.