Lucent Technologies Inc.

Alcatel Lucent

Alcatel-lucent USA Inc.

Terry Si-Fong Cheng

Ching Yao Huang

Frances Lin Jiang

Sudheer A Grandhi

Simon C Borst

Stanley Vitebsky

Boris Dmitrievich Lubachevsky

Qi Bi

John Kenney Burgess

Joe Huang

Dan Anthony Balogh

Yang Yang

Wen-Yi Kuo

Carl Francis Weaver

Krishnan Kumaran

Philip Alfred Whiting

Chih-Lin I

Asif Dawoodi Gandhi

Donna Michaels Sand

Bulin B Zhang

Balakrishnan Narendran

Yuen-Yin L Koo

Tomas S Yang

Martine Madelaine Herpers

Shen-De Lin

Joseph Samuel Kaufman

Bee Yun Yu

Lynell Earline Cannell

Michael Soellner

Adrian Robert Flewitt

Shawn S Yu

Ramakrishna Vishnuvajjala

Roland K Henter

Lindsey Chew

Nefatiti Anderson

Alexandro Federico Salvarini

Hans-Juergen Kettschau

Kevin John Murphy

The present invention provides a method of wireless communication using a mobile unit and first and second base stations. The method includes receiving, from the second base station, a notification of a switch of the first base station to the second base station. The method also includes providing at least one message to the second base station in response to receiving the notification.

Method of providing messages to a mobile unit on a forward link

The present invention provides a method and an apparatus for a wireless communication between a base station and at least one mobile station. The method includes receiving a request for a data rate from the mobile station on a reverse link channel to the base station. The method further includes, in response to the request, skipping a first slot after a delay for a portion of a slot on a forward link transmission before transmitting a data packet in a second slot. By beginning the forward link transmission at the start of the second slot, for example, a software module may cause the base station to skip a slot immediately after the half slot delay. This additional delay of one slot or a portion of the slot may expand radius of a cell for a wireless communication between the base station and the mobile station in a relatively high-speed wireless data network.

Expanding cell radius in a wireless communication system

A method for determining the reverse link data Rate Limit for mobile stations active on the reverse link of a High Data Rate system is disclosed. In the ideal case, the Rate Limit is based on only the number of mobile stations located in a common sector that are actually active on the reverse link. Currently, the Rate Limit is determined from the total number of mobile stations in a common sector where the total includes mobiles that are transmitting and receiving. Thus, the current method includes mobile stations that are active on the forward link and may not be active on the reverse link. In this invention, a more optimum method of estimating the reverse link loading is obtained from calculations which includes only the mobile stations which are active on the reverse link. An estimate of the reverse link loading of the mobile stations in a common cell is obtained by adding together the data rates of the data sent from each mobile in a common sector during a common frame. This aggregate rate of data during the frame is filtered to minimize irregularities by using the moving average of an infinite impulse response filter and then normalized. The normalized result is a percentage of the maximum achievable aggregate reverse link rate. The final result is compared with a set of threshold values to obtain the maximum Rate Limit that is then set for each mobile station.

Dynamic reverse link rate limit algorithm for high data rate system

The interference on the available communication frequencies is measured during an idle time slot over a first period of time at a first rate. The available frequencies are prioritized based on the interference measurements, and a list is formed of the frequencies having the lowest interference measurements. Interference measurements are made at a second rate, greater than the first rate, for a second period of time less than the first period. When a call is assigned, the interference level requirements for the call are given, and the carrier power level of the call is measured. The carrier-to-interference ratio of each frequency in the list is determined using the second interference measurements and the measured carrier power. The frequencies in the list meeting the interference level requirements for the call are then selected, and frequency hopping while serving the call is performed using the selected frequencies.

Method for frequency hopping in a TDMA wireless communication system

A code-division multiple access power control for paging channel power and initial traffic channel power dynamically determines optimum initial channel power in accordance with pilot signal strength of a pilot signal as received at a mobile station and current forward link loading of the desired sector. The optimum initial paging channel power and initial traffic channel power may be determined either at a base station or a mobile switching center of the mobile communication system. A paging signal or call is transmitted from the base station to the mobile station over a paging channel and a traffic channel at the optimum paging channel and initial traffic channel power.

CDMA power control for paging and initial traffic channel power

The present invention is a method for selectively providing, on demand, a Quality of Service level to an end user's data transmitted from a base station to a mobile station of a High Data Rate system. In the disclosed method, a data base is established which contains the Quality of Service level selected by a mobile user from a plurality of levels for data to be transmitted from the base station to the mobile station. Using the reverse link, an end user at a mobile notifies the base station that it is ready to receive data and specifies the rate at which the data is to be sent. Upon receipt of the request for data from the mobile terminal, the base station accesses and runs a scheduler which determines which user's data is to be transmitted next. For each end user, the scheduler divides the requested data rate by the average rate of data received by the mobile during a specific interval and then combines by adding or multiplying the result with the Quality of Service level requested by the end user for data. The end user that has the greatest final result is normally selected to next receive data. The scheduler then conditions the base station to transmit data to the identified mobile station at the requested rate and selected Quality of Service level.

Method of scheduling a quality of service level in a high data rate system

A method and apparatus for transmitting a burst of data over a supplemental channel on just one leg of a handoff by changing the maximum allowed burst duration of the data to be transmitted over the supplemental channel as a function of the future and/or current characteristics of the communication link of the leg(s) of the handoff. The data is then transmitted over just one leg of handoff using the maximum allowed burst duration. By changing the parameters of the data, the data may still be acceptably received at the mobile terminal over just one leg of the soft handoff even when the strength of the pilot signal used for the supplemental channel changes significantly. In an illustrative embodiment of the invention the stability of the communication link is used as a way of ascertaining the future conditions of the communications link.

Data transmission in a wireless communication system

In the method according to the present invention, a signal from a mobile station is received. The standard deviation of the symbol error rate is determined, and power control with adaptive adjustment of an amount of change in the target signal-to-noise ratio is performed based on the determined standard deviation of the signal error rate and a target associated therewith.

Method for enhanced power control by adaptively adjusting an amount of change in a target signal-to-noise ratio

A procedure for triggering a handdown or a handoff a mobile station served by a base station of a cellular wireless communication system. A tolerable path loss for signal links between the base station and a mobile station located within the base station's cell, is initially determined. A control signal is radiated at a known transmit power level from the base station over its cell. A receive power level threshold is determined for the control signal for reception by the mobile station, according to the transmit power level and the tolerable path loss. A handoff of the mobile station is triggered after deriving the received power level of the control signal at the mobile station, and determining that the received power level is less than the receive power level threshold. In one embodiment, a mobile station reports to a serving base station only after the former determines that the received power level of a control signal from the base station is less than a threshold level initially provided to the mobile station by the base station. The procedure is applicable, e.g., to base station cells of a first CDMA cellular system which cells border on cells of an analog (AMPS) or a second CDMA cellular system.

Triggering handdowns and handoffs of mobile stations between bordering cells of cellular wireless communication systems

Disclosed is a method for improving call quality and capacity by integrating a dynamic channel allocation technique into an intelligent antenna system. The intelligent antenna systems includes beams which are grouped into sets, wherein each set has associated a long list and a primary short list, and each beam has associated a secondary short list. In one embodiment, long term interference levels are measured on each beam in a set of beams for a plurality of communication channels to produce the long list; short term interference levels are measured on each beam in the set of beams for a portion of the plurality of communication channels to produce a plurality of secondary short lists and the primary short list; and communication channels are assigned to a mobile-station from the portion of the plurality of communication channels based on the measured short term interference levels on each beam in the set of beams. The long list and the primary short list are based upon highest measured long and short term interference levels, respectively, for each of the plurality of communication channels across each beam in the set of beams.

Dynamic channel assignment for intelligent antennas

The present invention, in illustrative embodiments, implements systems and methods for adjusting the timing of access requests in mobile communications systems, such as IS-95-A mobile telephone systems, to reduce the likelihood of request collisions&mdash;especially during periods of very high calling rates. These embodiments employ measurements of access channel occupancy, as well as system operator inputs, to develop thresholds and parameter translations at a base station. Execution of control algorithms at a base station advantageously yields modified persistence test parameters sent to mobile stations. When overload conditions are present, these modified parameters cause the mobile stations to experience variable delays through judicious control of persistence testing at the mobile stations.

System and method for variably delaying access requests in wireless communications system

A code-division multiple access base station assisted quality soft handoff algorithm screens or filters out candidate pilot signals from a pilot strength measurement message generated by a mobile station and provides the revised pilot strength measurement message to the mobile switching center of the mobile communication system. The mobile switching center subsequently conducts handoff processing in accordance with the revised pilot strength measurement message. If the combined pilot signal strength of the existing mobile station active legs is less than a first threshold, the current pilot strength measurement message is maintained. If the combined pilot signal strength of the existing mobile station active legs is greater than or equal to the first threshold, all candidate pilot signals are deleted from the pilot strength measurement message such that only pilot signals of existing mobile station active legs remain. Also, if the pilot signal strength of a candidate pilot signal is greater than a second threshold, the candidate pilot signal is added to the pilot strength measurement message. The number of handoffs per call are reduced using the revised pilot strength measurement message such that forward link power and network processing resources are conserved.

CDMA base station assisted soft handoff

Call processing overload at a base station of a cellular wireless network is controlled by monitoring a level of call processing at the base station, and reducing a present handoff rate for active users when the call processing level exceeds a first threshold less than a maximum call processing capacity. When the call processing level at the base station exceeds a second threshold greater than the first threshold, a present rate of call originations or terminations is reduced while further reducing the handoff rate.

Processing overload control at base stations of cellular wireless communication systems

Link performance is measured in a code division multiple access (CDMA) personal communication service (PCS) or cellular system, or other type of wireless system, using a test set-up which permits the simulation of various changes in system configuration. An illustrative embodiment includes a first attenuator arranged in a common portion of a receive path and a transmit path of a mobile station of the system, and a second attenuator arranged in either a receive-only portion of the receive path or a transmit-only portion of the transmit path. The amounts of attenuation provided by the first and second attenuators are decoupled such that a different amount of attenuation can be provided on the transmit path than on the receive path. Performance of forward and reverse links of the system are measured while varying a value of at least one of the first or second attenuators. For a given measurement, the attenuator values may be selected to simulate performance of the system in a configuration in which base station amplifier power is increased or decreased. As another example, the attenuator values may be selected to simulate performance of the system in a configuration in which cell size is increased. This arrangement of decoupled forward and reverse link attenuation in accordance with the invention permits efficient and accurate determination of link balance conditions.

Methods and apparatus for determining forward and reverse link

Operations in a cellular system are controlled based on cost values that are generated using neighbor association. In neighbor association, each cost value corresponds to a cost of assigning a candidate channel to a first cell in the cellular system, assuming that the candidate channel is already assigned to a second cell in the cellular system and each cost value is based on an average power attenuation for all of the cells in the cellular system that share the same tier as the second cell with respect to the first cell, wherein the average power attenuation is based on the reuse distances between the first cell and the cells in the same tier. In one embodiment, the cost values are used in a cost-function-based dynamic channel assignment (DCA) algorithm that is, but does not have to be, applied to a list of candidate channels generated using a measurement-based DCA algorithm.

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Singapore, Singapore

Terry Si-Fong Cheng