Abstract: A method of hitless switching over a communications link, the method comprising transmitting, by a first modulator to a remote receiver, a first carrier signal having a first center frequency, enabling, by a second modulator to the remote receiver, transmission of a second carrier signal having a second center frequency while the first modulator is transmitting the first carrier signal, increasing, through the second modulator, a power level of the second carrier signal while the first carrier signal is transmitting, simultaneously decreasing, through the first modulator, a power level of the first carrier signal while the power level of the second carrier signal is increasing, and disabling transmission of the first carrier signal to the remote receiver when the power level of the second carrier signal reaches a predetermined level.

Abstract: A method of hitless switching over a communications link, the method comprising transmitting, by a first modulator to a remote receiver, a first carrier signal having a first center frequency, enabling, by a second modulator to the remote receiver, transmission of a second carrier signal having a second center frequency while the first modulator is transmitting the first carrier signal, increasing, through the second modulator, a power level of the second carrier signal while the first carrier signal is transmitting, simultaneously decreasing, through the first modulator, a power level of the first carrier signal while the power level of the second carrier signal is increasing, and disabling transmission of the first carrier signal to the remote receiver when the power level of the second carrier signal reaches a predetermined level.

Abstract: A communication device may obtain a channel estimate, and may adjust power thresholds governing an adaptive bit loading scheme. The communication device may include a transceiver arranged to receive data from a remote transmitter on a plurality of subcarriers. The communication device may also include a controller coupled to the transceiver. Finally, a memory unit may be coupled to the controller. The memory unit may contain a set of instructions that when executed cause the controller to cooperate with the transceiver to create a channel estimate, to create modulation criteria based at least in part on the channel estimate, and to command the remote transmitter, on a subcarrier-by-subcarrier basis, to employ a particular modulation technique on a particular subcarrier. Such a command may be based at least in part on a comparison of the channel estimate and the modulation criteria.

Abstract: Dynamic guard interval adaptation is provided for devices having differing delay spreads in an OFDM communication system to reduce the guard intervals, with adaptation controlled by either the wireless communications device or the network.

Abstract: A circuit and method provides subcarrier puncturing by placing no information in subcarriers that suffer from channel impairments where they cannot deliver information. If no energy is placed in these subcarriers, then the transmitted power may be re-allocated to the information carrying subcarriers to increase the Signal-to-Noise Ratio (SNR) at the target node. Or, energy may be place in subcarriers that suffer from channel impairments, but the PAPR of the OFDM symbol may be reduced.

Abstract: An apparatus may include an orthogonal frequency division multiplexing (OFDM) physical layer interface. An adaptive subcarrier demodulator or an adaptive subcarrier modulator may be coupled to the OFDM physical layer interface to implement adaptive bit loading (ABL). A decoder or an encoder may be coupled to the adaptive subcarrier demodulator or to the adaptive subcarrier modulator to implement low density parity checking.

Abstract: Dynamic guard interval adaptation is provided for devices having differing delay spreads in an OFDM communication system to reduce the guard intervals, with adaptation controlled by either the wireless communications device or the network.

Abstract: A circuit and method provides subcarrier puncturing by placing no information in subcarriers that suffer from channel impairments where they cannot deliver information. If no energy is placed in these subcarriers, then the transmitted power may be re-allocated to the information carrying subcarriers to increase the Signal-to-Noise Ratio (SNR) at the target node. Or, energy may be place in subcarriers that suffer from channel impairments, but the PAPR of the OFDM symbol may be reduced.

Abstract: Expandable intraluminal prostheses for the treatment of aneurysmal disease or occlusive disease at a bifurcation of a vessel, duct, or lumen, e.g, disease at the aorto-iliac bifurcation. Each prosthesis includes three expandable, sleeve sections which are arranged to be located in respective portions of the vessel, duct, or lumen contiguous with the bifurcation, and secured together in situ. The prosthesis for aorto-iliac aneurysmal disease includes a common, stent-supported sleeve section having an expandable outer balloon for engaging and trapping the thrombus in the aneurysmal space in the abdominal aorta, and a pair of stent-supported sleeve limb sections. The limb sections are connected to the common section to provide a passage for blood to flow through the prosthesis. One or more of the limb sections can also include a outer balloon for engaging the thrombus within its associated aneurysmal space.

Abstract: An intraluminal prosthesis for use in a blood vessel, e.g., the abdominal aorta, at which an aneurysm defining an aneurysmal space is located. The prosthesis basically comprises an expandable sleeve, an outer balloon, a pair of sealing rings or a sealing cover, a pair of expandable anchoring stents, and plural expandable support stents. The sleeve is an elongated tubular member defining a passageway having a pair of open ends for conveying blood therethrough. The outer balloon is disposed about the sleeve and is arranged to be filled with a fluid, e.g., a gel or saline, to cause it to extend outward to fill the aneurysmal space. The sleeve is arranged to be expanded and held in that state by the stents.

Abstract: An endovascular graft for securement within a vessel, duct, or lumen of a living being. The graft comprises a tubular graft sleeve and a plurality of ring-like stents mounted on the outer surface of the sleeve. Anchoring projections are provided on the outer surface of the stents. The graft sleeve has a passageway extending therethrough, which when-the graft is located within the vessel, duct, or lumen serves to carry body fluid, e.g., blood, through it in a single direction. This action produces a force on the tubular sleeve and the plural stents mounted thereon. The anchoring projections extend outward from the outer surface of the stents and are arranged for engagement with the interior of the wall of the vessel, duct, or lumen. The anchoring projections are preferentially oriented to include portions extending at an acute angle to the direction of the fluid flow to tightly engage the interior of the wall of the vessel, duct, or lumen under the force applied by the fluid flowing through the device.

Abstract: An intraluminal graft for placement in a blood vessel, duct, or lumen, to hold it open. The graft comprises a sleeve having plural stents thereon. The sleeve is an elongated tubular member formed of a conventional graft material which is flexible and impervious to the ingrowth of tissue therein. Each stent is a generally ring-like member formed a plurality of interconnected movable links and is mounted about the periphery of a surface, e.g., inner or outer, of the sleeve at selected points along the sleeve to form respective spaced first sleeve sections. Each of the first sections extends for only a portion of the length of the graft, thereby leaving a plurality of second sleeve sections interposed between the first sleeve sections. The stents and the sleeve are arranged to be expanded, e.g., by a balloon catheter, from a compact state to an expanded state to increase the inner cross sectional area diameter of the sleeve. In the expanded state the stents are resistant to contraction back to the compact state.