Abstract: A first communication device receives a plurality of training signals from a second communication device via a communication channel. The first communication device determines, based on the plurality of training signals, a channel matrix corresponding to the communication channel, and determines, based the channel matrix and without decomposing a steering matrix, compressed feedback to be provided to the second communication device. The first communication device transmits the compressed feedback to the second communication device to enable the second communication device to steer at least one subsequent transmission to the first communication device.

Abstract: Methods and systems are disclosed herein for performing channel estimation for multi-stream packets. The method may include receiving a data packet comprising a plurality of training fields, wherein the plurality of training fields comprises a training field, wherein the training field comprises a plurality of tones, and wherein the plurality of tones comprises a first tone and a second tone. The method may include modifying the first tone based on a predetermined signal associated with the first tone. The method may include storing the first tone in a data structure associated with the first tone. The method may include modifying the data structure based on the second tone.

Abstract: Disclosed are refrigerants comprising at least about 97% by weight of a blend of three compounds, said blend consisting of: from about 40% by weight to about 49% by weight difluoromethane (HFC-32), from about 6% by weight to about 12% by weight pentafluoroethane (HFC-125), from about 33% by weight to about 40% by weight trifluoroiodomethane (CF3I); and from about 2% by weight to about 12% by weight of trans 1,3,3,3-tetrafluoropropene (trans HFO-1234ze), wherein the percentages are based on the total weight of the three compounds in the blend, and systems and method using same.

Abstract: Disclosed are refrigerants comprising at least about 97% by weight of a blend of three compounds, said blend consisting of: from about 38% by weight to about 48% by weight difluoromethane (HFC-32), from about 6% by weight to about 12% by weight pentafluoroethane (HFC-125), from about 33% by weight to about 41% by weight trifluoroiodomethane (CF3I) and from about 2% by weight to about 16% by weight 2,3,3,3-tetrafluoropropene (HFO-1234yf) wherein the percentages are based on the total weight of the three compounds in the blend, and methods and systems which use same.

Abstract: Disclosed are cascade refrigerant systems for providing cooling of air located in an enclosure that is occupied by or which will be exposed to humans or other animals during normal use, wherein systems includes; (1) a first, relatively low temperature heat transfer circuit having a first evaporator located within the enclosure and a first heat transfer fluid in the low temperature heat transfer circuit; (2) a second heat transfer circuit located substantially outside the enclosure comprising a second heat transfer fluid; (3) a heat exchanger which serves as the condenser in the low temperature circuit thermally coupled with the high temperature circuit by virtue of rejecting heat into the second heat transfer fluid; and (4) in the high temperature loop of a heat exchanger which transfers heat from the second heat transfer fluid exiting from a high temperature condenser to the portion of the second heat transfer fluid which is traveling to the suction side of the compressor.

Abstract: Embodiments described herein provide a method for carrier frequency offset and frequency drift cancellation based indoor position estimation. A wireless signal including a plurality of data samples is received at a receiving antenna and from a mobile device. Information relating to an antenna switching pattern for transmitting or receiving the wireless signal may then be obtained from the wireless signal. A phase difference is calculated associated with each data sample of plurality of data samples. Carrier frequency offset and frequency drift cancellation may be applied to the phase difference to obtain a compensated phase difference. A direction estimate of the mobile device may then be generated based at least in part on the compensated phase difference.

Abstract: The present invention relates, in part, to heat transfer compositions, and associated systems and methods, which include a first composition selected from the group consisting of HFO-1233zd, HFC-245fa, and combinations of these; and, optionally, a second composition selected from the group consisting of HFO-1234ze, HFC-134a, and combinations of these.

Abstract: The present invention relates to a refrigerant composition, including difluoromethane (HFC-32), pentafluoroethane (HFC-125), and trifluoroiodomethane (CF3I) for use in a heat exchange system, including air conditioning and refrigeration applications and in particular aspects to the use of such compositions as a replacement of the refrigerant R-410A for heating and cooling applications and to retrofitting heat exchange systems, including systems designed for use with R-410A.

Abstract: The present invention relates, in part, to heat transfer compositions and methods that include (a) from about 65% to about 75% by weight of HFC-32; (b) from about 15% to about 35% by weight of a compound selected from unsaturated —CF3 terminated propenes, unsaturated —CF3 terminated butenes, and combinations of these; and (c) from greater than about 0% to less than about 10% by weight of CO2, provided that the amount of component (c) is effective to improve heating capacity of the composition and reduce the defrost cycle in refrigerant applications, as compared to compositions lacking this component.

Abstract: Systems and methods described herein provide a method for detecting beamformed detecting beam-formed orthogonal frequency division multiplexing (OFDM) packets. The method includes receiving, at a receiver, a data signal including a data packet, and selecting a set of frequency domain tones associated with the data signal for channel estimation. The method further includes calculating a plurality of differential parameters between adjacent frequency domain tones from the set of frequency domain tones. The method further includes identifying a jump when a first differential parameter from the plurality of differential parameters exceeds a jump threshold. The method further includes obtaining an accumulative count of jumps for the set of frequency domain tones, and identifying the data packet is beamformed when the accumulative count exceeds a jump limit.

Abstract: Disclosed are refrigerant systems for conditioning air and/or items located within a dwelling occupied by humans or other animals preferably including at least a first heat transfer circuit containing a first heat transfer fluid in a vapor/compression circulation loop located substantially outside of the dwelling and at least a second heat transfer circuit, which contains a second heat transfer fluid different than the first heat transfer fluid, located substantially inside of the dwelling. In preferred embodiments, the second heat transfer circuit does not include a vapor compressor, but the system includes at least one intermediate heat exchanger which permits exchange of heat between the first heat transfer fluid and the second heat transfer fluid such that heat is transferred to the first heat transfer fluid, preferably thereby evaporating the first heat transfer fluid, and from the second heat transfer fluid, thereby condensing the second heat transfer fluid.

Abstract: Disclosed are refrigeration systems of the type having a heat source to be cooled and a heat sink into which heat can be rejected, said system preferably having a capacity of from about 2 to about 30 tons and comprising: (a) a heat transfer composition comprising a refrigerant comprising at least about 80% by weight of trans1-chloro-3,3,3-trifluoropropene (HCFO-1233zd(E)) or at least about 80% by weight of trans1,3,3,3-tetrafluoropropene (HFO-1234ze(E)); (b) a centrifugal compressor having: (i) a refrigerant suction for receiving a relatively low-pressure refrigerant vapor at a pressure of from about 40 to about 350 kPa and (ii) a discharge for discharging a relatively high pressure refrigerant vapor at a pressure wherein the discharge:suction pressure ratio is at least about 2:1; (c) a condenser operating at temperature in the range of from about 10° C. to about 60° C.

Abstract: A device includes a frequency offset (FO) estimation circuit and a frequency offset compensation circuit coupled with the frequency offset estimation circuit. The frequency offset compensation circuit is configured to (i) receive a continuous phase modulation (CPM) signal, (ii) receive, from the FO estimation circuit, an uncompensated frequency offset for a wth sampling window of the CPM signal, (iii) generate a frequency offset compensation value for a w+1st sampling window of the CPM signal based on the uncompensated frequency offset for the wth sampling window, (iv) adjust the CPM signal in the w+1st sampling window based on the frequency offset compensation value, and (v) provide the adjusted CPM signal to a filter.

Abstract: The present invention relates, in part, to heat transfer and refrigerant compositions and methods that include HFC-32; HFO-1234ze and HFC-125.

Abstract: Disclosed are methods of recharging an operating system of the type containing a less than full charge of existing working fluid with a recharging fluid that is different than said existing fluid, the method comprising: (a) identifying at least one readily measured physical property of fluids comprising combinations of the existing working fluid and the recharging working fluid wherein said physical property reliably correlates to target component concentrations of the working fluid after recharge; (b) providing a system which contains less than a full charge of the existing working fluid; (c) adding to the existing working fluid a recharging fluid having at least one property superior to that property of the existing working fluid; (d) at least after said adding step (c), measuring said readily measured physical property of the operating fluid in the system; and (e) based on said measuring step, repeating or not said steps (c) and (d) and/or adjusting at least one system operating parameter.

Abstract: The present invention relates, in part, to heat transfer and refrigerant compositions and methods that include HFC-32; HFO-1234ze and HFC-125.

Abstract: The present invention relates, in part, to heat transfer compositions, and associated systems and methods, which include a first composition selected from the group consisting of HFO-1233zd, HFC-245fa, and combinations of these; and, optionally, a second composition selected from the group consisting of HFO-1234ze, HFC-134a, and combinations of these.

Abstract: Heat transfer compositions, methods, and systems including (a) HFC-32; (b) HFO-1234ze; and (c) either HFC-152a. In certain aspects, such compositions include (a) from about 33% to about 70% by weight of HFC-32; (b) from about 20% to about 66% by weight of HFO-1234ze; and (c) from greater than about 0% to about 30% by weight of HFC-152a. The amount of each of the components (a), (b) and (c) may be selected to ensure that the burning velocity of the composition is less than about 10, the global warming potential of the composition is less than about 500, wherein said composition exhibits a COP of within 5% of R22 in an air conditioning system operated at an ambient temperature of at least 35° C.

Abstract: The present invention relates, in part, to heat transfer compositions, and associated systems and methods, which include a first composition selected from the group consisting of HFO-1233zd, HFC-245fa, and combinations of these; and optionally, a second composition selected from the group consisting of HFO-1234ze, HFC-134a, and combinations of these.

Abstract: The present invention relates, in part, to heat transfer and refrigerant compositions and methods that include HFC-32; HFO-1234ze and HFC-125.