Nortel Networks Corporation

Ericsson Ab

Apple Inc.

Rockstar Bidco, LP

Daniel Boudreau

Wen Tong

Jianming Wu

Christian Dubuc

Mo-Han Fong

Peiying Zhu

Ming Jia

Hua Xu

Shiquan Wu

Keith Russell Edwards

William R Kirkland

David G Steer

Koon Hoo Teo

John Edward Hudson

Bassam M Hashem

John J O'Hara

James A Philippou

J Martin Borden

Colin Brown

Kerry M Hannigan

Shawn Mamros

Bernard Farrell

A method of allocating bandwidth is provided which involves for each sector of a plurality of sectors in a cell, using a respective subset of a total bandwidth; wherein for any two adjacent sectors, the respective subsets only partially overlap. A scheduling method is provided which involves for each sector, scheduling users for transmission on the respective subset of the total bandwidth by: for a given transmitter, allocating a respective fraction of capacity associated with the available bandwidth to each of at least two users selected from a plurality of users by performing an optimization for a selected scheduler design, the optimization selecting the at least two users and the optimization determining for each user the respective fraction of capacity; generating and transmitting a signal in which each of the at least two users has the respective fraction of capacity.

Systems and methods for channel allocation for forward-link multi-user systems

A transmitter () generates a first set of data symbols and a first pilot symbol () at a first time, and a second set of data symbols and a second pilot symbol () at a different, second time. The first () and second () pilot symbols are each represented by first () and second () pilot carriers, respectively, located at first () and second () predetermined sample frequencies, respectively, in a channel bandwidth. For the first pilot symbol (), the first () and second () pilot carriers have first and second predetermined values, respectively. For the second pilot symbol (), the first () and second () pilot carriers have third and fourth predetermined values, respectively. A receiver () measures the first, second, fourth and third predetermined values responsive to receiving the first () and second () pilot symbols to determine first, second, third and fourth estimates of channel distortion, respectively, for compensating and recovering the first and the second sets of data symbols.

System and method for I/Q imbalance compensation

Systems and methods of combining OFDM and CDMA signals are provided. An OFDM packet data channel is overlaid over CDMA transmissions. The channel is scheduled slotwise between multiple users. In some embodiments, there is a CDMA packet data channel which is scheduled together with the OFDM packet data channel.

Receiver for receiving embedding OFDM in an CDMA systems

Method for embedding OFDM in CDMA systems

A transmitter () generates a first set of data symbols and a first pilot symbol () at a first time, and a second set of data symbols and a second pilot symbol () at a different, second time. The first () and second () pilot. symbols are each represented by first () and second () pilot carriers, respectively, located at first () and second () predetermined sample frequencies, respectively, in a channel bandwidth. For the first pilot symbol (), the first () and second () pilot carriers have first and second predetermined values, respectively. For the second pilot symbol (), the first () and second () pilot carriers have third and fourth predetermined values, respectively. A receiver () measures the first, second, fourth and third predetermined values responsive to receiving the first () and second () pilot symbols to determine first, second, third and fourth estimates of channel distortion, respectively, for compensating and recovering the first and the second sets of data symbols.

The present invention provides different scheduling criteria depending on overall system performance in an effort to maintain fairness among mobile terminals and sustain a required QoS level. The invention is particularly effective for multi-carrier systems, wherein scheduling must also take into consideration the carrier used to transmit the scheduled data. In one embodiment, the present invention determines the spread of throughput rates for all mobile terminals being served by a given base station and bases the scheduling criteria thereon. Preferably, a standard deviation calculation is used to measure the throughput spread. The standard deviation of throughput associated with a collective group of mobile terminals is indicative of the differences between the lowest and highest throughputs with respect to the average throughput for the collective group of mobile terminals.

Multiple threshold scheduler

The present invention divides the available sub-carriers in an OFDM symbol window into N groups of sub-carriers wherein each group will be associated with sub-bands. In one embodiment, the sub-carriers in a group are spread throughout the range of sub-carriers to improve frequency diversity, and the sub-carriers assigned to any one group are separated by a constant offset. The sub-carriers in the group may be offset by an integer power of two. Within each group, sub-bands are defined using frequency hopping patterns among sub-carriers in the group from one OFDM symbol window to another. A pseudo-random pattern may be employed for sub-carrier mapping from one OFDM symbol window to the next to effectively distribute the sub-bands across the selected band of sub-carriers for the group.

Sub-carrier allocation for OFDM

System and method for embedding OFDM in CDMA systems

It is becoming increasingly important to improve data throughput in wireless networks. By transmitting data simultaneously at different modulation amplitudes and/or using different code strengths, terminals having different carrier to noise ratios are able to decode the different amplitude levels with varying degrees of success. This allows distant terminals to receive low data rate transmissions at high modulation levels or code rates while nearer terminals can use additional capacity in the transmission by receiving lower level modulation signals or code rates. In this way, distant terminals do not degrade overall network performance. By arranging for terminals to acknowledge receipt of data, retransmission at different modulation levels or code rates may be carried out by the base station in order to improve performance in the presence of noise without a priori knowledge of the carrier to noise ratio for a particular terminal.

Methods and apparatus for transmitting and receiving data over a communications network in the presence of interference

The present invention is a method and apparatus to balance load in a cluster of switches in a network. The switches include a local switch and one or more remote switches. Messages containing load information of the switches are exchanged among the switches. One of the switches is selected to respond to a connection request to the local switch based on a metric.

Network switch load balancing

Growing community of inventors

Hull, Canada

Daniel Boudreau