Abstract: Noise variance estimation in wireless communications. Noise variance estimation includes receiving a signal including an OFDM symbol having, in-band tones including in-band pilot tones, and band-edge tones including band-edge pilot tones and guard tones, estimating an effective noise variance for the in-band tones using the in-band pilot tones and channel estimates for the in-band pilot tones, and estimating an effective noise variance for the band-edge tones using the band-edge pilot tones, channel estimates for the band-edge pilot tones, and the guard tones.
Type:
Grant
Filed:
January 28, 2005
Date of Patent:
March 2, 2010
Assignee:
Qualcomm Incorporated
Inventors:
June Namgoong, Hao Xu, Peter J. Black, Srikant Jayaraman
Abstract: The present apparatus comprises a radio access network element having at least one processor, and at least one memory operably connected to the at least one processor, whereby the radio access network element is adapted to execute instructions stored in the memory comprising discovery of at least one other element in a radio access network. The radio access element further comprises instructions for removal or addition of network elements, instructions for determining a paging area and instructions for forwarding messages from a mobile to a controller in another domain.
Type:
Grant
Filed:
February 3, 2006
Date of Patent:
December 15, 2009
Assignee:
Qualcomm Incorporated
Inventors:
Paul E. Bender, Noam A. Ziv, Vito Bica, Rahul Anand, Sreekanth Vietla
Abstract: In a system including a resource which is shared among a number of users, it is difficult to distribute the available capacity of the resources fairly among the users and still maximize resource utilization. Additionally, it is desirable to allow at least some of the control over usage rates to remain with the users, while at the same time avoiding situations where the resource is overloaded. A system and method are disclosed wherein usage rates are selected from among a set of available rates according to a set of persistence vectors.
Type:
Grant
Filed:
June 1, 2007
Date of Patent:
October 6, 2009
Assignee:
QUALCOMM Incorporated
Inventors:
Gadi Karmi, Matthew Stuart Grob, Paul E. Bender
Abstract: A method and a power control device moving the resynchronisation point within the guard period to coincide with a calculated reduction in the RF PA power level such that the spurious frequency products are attenuated as much as possible and moved to be as central as possible within the guard period such that neither the previous burst nor the next burst are affected.
Type:
Grant
Filed:
May 23, 2005
Date of Patent:
June 9, 2009
Assignee:
QUALCOMM Incorporated
Inventors:
Julie Stuart, legal representative, Zhi-Zhong Yu, Alan Andrew Smith
Abstract: According to a disclosed embodiment, a first plurality of pilot signals of a first polarization is received and ranked. Subsequently, a second plurality of pilot signals of a second polarization is received and ranked. Following, a pilot signal from the first and second pluralities of pilot signals is selected based on a signal quality measurement such as a signal to interference ratio. Moreover, a system can be constructed comprising antennas configured to receive pilot signals of a first and a second polarization. The system further comprises a receiver configured to demodulate the pilot signals and a CPU configured to rank the pilot signals and to select a pilot signal based on a signal quality measurement. Communication quality is improved by communicating with the base transceiver station transmitting the pilot signal providing the highest signal quality measurement.
Abstract: An apparatus for providing a Time Division Multiplexing (TDM) scheme for link adaptation including use of channel estimation and Channel Quality Indicator (CQI) measurements by bundling several timeslots of a frame within the existing GSM/GPRS/EDGE system. An algorithm for providing rotation of MS users such that each one will benefit from measuring all timeslots of the frame resulting in more reliable and accurate transmission of information.
Type:
Grant
Filed:
May 19, 2004
Date of Patent:
February 3, 2009
Assignee:
QUALCOMM, Incorporated
Inventors:
Lorenzo Casaccia, Durga Prasad Malladi, Francesco Grilli
Abstract: A system to communicate a superposition coded packet from a base station to a plurality of remote stations. At the base station, from a list of user candidates for superposition coding a most deserving user may be determined. Those user candidates with a requested data rate less than that of the most deserving user may be eliminated. A superposition coded packet may be compiled from the remaining user candidates. On receipt, the most deserving user may process the superposition coded packet by assuming a predetermined power allocation. Further, if a user successfully in decodes early, power may be re-allocated to another user.
Abstract: The punctured pilot channel comprises information symbols of uncertain sign punctured into a sequence of pilot channel symbols of predetermined sign. The apparatus includes an information sign demodulation circuit for determining the sign of the information symbols in response to the pilot channel symbols. A continuous pilot generator generates a non-punctured pilot channel of predetermined sign from the information symbols and the pilot channel symbols. In a first embodiment, the information sign demodulator further comprises a dot product circuit for calculating a dot product of the pilot channel symbols and the punctured information symbols, and a threshold comparator for comparing the dot product to a predetermined threshold.
Abstract: A method and apparatus for transmitting broadcast information in a multi-carrier communication system. The Sync Channel of the multi-carrier system is transmitted a 1.25 MHz channel bandwidth (i.e., over a single carrier), and to specify the preferred channels for the Sync Channel transmission instead of the preferred channels for the entire multi-carrier system. The Sync Channel Message will carry additional information indicating the center frequency of a multi-carrier system within a reserved set of frequency bands and indicating the frequency of a single carrier system in the reserved set of frequency bands. Considering the A block of the PCS band again, the preferred channels for Sync Channel transmission can be selected as channels 75, 150 and 225. This selection ensures that one of the preferred channels will always be used by any multi-carrier system regardless of the location of its center channel.
Abstract: First and second transmission links are established with a remote station. An information signal is encoded to provide an encoded information signal having more bits than the information signal. First and second transmission signals are provided wherein each transmission signal has bits selected from the encoded information signal. Each of the first and second transmission signals is transmitted to the remote station by way of a respective one of the first and second transmission links. The remote station receives and combines the first and second transmission signals transmitted by the remote station to provide a combined encoded signal. The combined encoded signal is decoded by the remote station to provide the information signal. The first and second transmission links can be formed between the remote station and a single base station or between the remote station and two separate base stations.
Abstract: Method and apparatus for reducing interference in a wireless communication system when the source of interference is a deterministic component of the system. In one embodiment, the receiver weights the transmitters according to when the source of interference is transmitted. Further, the transmitter may employ power boosting to overcome the source of interference. In one embodiment, a W-CDMA system transmits a sync channel concurrently with physical channels, wherein the sync channel is not orthogonal to the physical channels. The receiver may cancel the sync channel when receiving control or data information. Similarly, the receiver may weight the transmissions from multiple transmitters.
Type:
Grant
Filed:
April 8, 2002
Date of Patent:
July 29, 2008
Inventors:
Serge Willenegger, Durga P. Malladi, Josef J. Blanz
Abstract: Disclosed is a refrigerating system which retrieves energy lost when the pressure necessary to make refrigerant flowing is changed from high pressure to low pressure and reuses the energy as a power source for increasing the pressure again, thereby reducing the amount of energy used in the refrigerating system and improving the performance of the system. The refrigerating system including a condenser, an expansion valve, an evaporator and a compressor is provided with a plurality of magnet valves connected to the output part of the compressor and the output part of the condenser for measuring the temperature and pressure of a part of the refrigerant discharged from the compressor and condenser; a plurality of by-pass pipes for by-passing the part of the refrigerant to the compressor; and an ejector connected to the by-pass pipes for ejecting the part of the refrigerant fed from evaporator back to the compressor based on the venturi principle.