Lucent Technologies Inc.

Other

Intel Corporation

At+t Corp.

Lucent Technology

Alcatel Lucent

Wen-Yi Kuo

Martin Howard Meyers

Carl Francis Weaver

Raafat Edward Kamel

Qi Bi

Xiao Cheng Wu

Kiran Meghashyam Rege

Sarath Kumar

Tsao-Tsen Chen

Frances Lin Jiang

Mathew Thomas

Yuen-Yin L Koo

Edward Ellis Eibling

Sirin Tekinay

Neil E Bernstein

Joseph E Cloutier

Xiao C Bernstein

Xiao Wang

Semyon B Mizikovsky

Ching Yao Huang

Jie Lai

Terry Si-Fong Cheng

James Paul Seymour

Ming Lu

Gang Li

Tejaskumar R Patel

Shen-De Lin

Charles Albert Sanders

Tai-Ann Chen

Sudhir Ramakrishna

Mjing Lu

Asif Dawoodi Ganhi

Methods and systems are provided to control transmit power in a wireless transmitter. By receiving a number of transmit control protocol (TCP) segments, converting the TCP segments to radio link control (RLC) frames and transmitting the RLC frames based on a predetermined targeted frame error rate, the initial RLC frames are transmitted using a minimum of power. Any unsuccessfully transmitted RLC frames are cyclically re-transmitted, along with a number of new RLC frames, at decreasing targeted frame error rates, until all RLC frames in a given transmission cycle are successfully transmitted. Accordingly, a new block of RLC frames are transmitted at the predetermined maximum targeted frame error rate. By transmitting RLC frames in this fashion, the overall transmit power can be reduced as compared to conventional transmission techniques, while increasing total data throughput.

Error-rate management in wireless systems

A method and apparatus to estimate the channel fade (both the amplitude gain/loss and the phase rotation) to assist the receiver to detect and recover the transmitted signal employs a continuous pilot signal such as the pilot code channel or pilot symbols. The channel estimator uses the same scrambling pattern of pilot channel and coherently integrates the continuous pilot signal to yield a channel estimate. The present invention employs adaptive integration duration to yield a channel estimate. The integration duration of the pilot signal for channel estimation is adaptive and proportional to the Doppler period. The Doppler period is proportional to the inverse of Doppler frequency and is an indicator of how fast the channel changes.

Adaptive channel estimation using continuous pilot signal based on doppler period

A method and apparatus that permits base stations to adaptively set initial power levels in forward link traffic channels (i.e., base station to mobile unit) based on an interference measure, where the interference measure is the difference between the base station transmitted pilot E/Iand the mobile unit received pilot E/I. The interference measure indicates how much interference is present from other base stations in the mobile unit's locale, mobile receiver noise and other similar sources. Call quality and system capacity are optimized since the initial power level is set in accordance with the interference environment. The method of the invention implements the adaptive setting by extracting the mobile unit received pilot E/Ifrom the access message transmitted by the mobile unit. The interference measure is then determined and used by the base station to set the initial power level in the forward link traffic channel.

Method and apparatus for adaptive setting of initial traffic power

A method for reducing multiple dominant pilots in a CDMA transmission system comprises linking a transceiver element with a nearby base station for transporting signals between the transceiver element and the nearby base station. Transmitting from the transceiver element forward link signals of a nearby sector associated with the nearby base station. An apparatus is also described.

Methodology of reducing areas with multiple dominant pilots by installing simulcasting elements or omni-directional base station

According to an embodiment of the invention, the information is transmitted in symbols encoded at a source to a destination. A log likelihood ratio is respectively calculated for each of the encoded symbols. The calculated log likelihood ratios for the information bits are accumulated where the contribution from each of the encoded symbols is accounted for in the accumulating step. Each of the information bits is decoded according to the accumulated log likelihood ratios. An acknowledgment (ACK) is sent to the source for each block of the decoded information bits that passed the error check. A negative acknowledgment (NACK) is sent to the source for each block of the decoded information bits that did not pass the error check. After the source receives the negative acknowledgment (NACK), the encoded symbols are retransmitted to the destination.

Methods and apparatus of signal demodulation combining with different modulations and coding for wireless communications

Methods and apparatus for estimating mobile station location in a wireless communication system. At initiation of a call or a page response, a mobile station of the system sends an access request signal to a primary base station. The primary base station responds with an access acknowledgment which may be intentionally delayed such that the mobile station increases its transmit power level. The primary base station then transmits a channel assignment message to the mobile station. The mobile station responds by transmitting a location signal in the form of a known user-specific traffic preamble at the higher transmit power level. The primary base station intentionally delays sending an acknowledgment of the preamble, such that the mobile station transmits the preamble for a longer period of time than it would otherwise. This additional transmission time allows the preamble to be detected accurately in the primary base station as well as in a number of other surrounding base stations in a manner suitable for generating path delay measurements. A primary location processor associated with the primary base station uses the path delay measurements from the primary and surrounding base stations to generate an estimate of mobile location. The mobile location estimation may be provided during an on-going call by the primary base station sending a fake handoff message to the mobile station directing it to handoff to the same base station and traffic channel but with a different power level and preamble length, or by the primary base station sending a predetermined location probe message directing the mobile station to transmit the traffic preamble with a desired power level and preamble length.

Mobile location estimation in a wireless communication system

In a system of communication, a sending node sends a message to a receiving node, which NAKs unsuccessful transmissions. The sending node screens the NAKs to determine if they were sent before the receiver could receive previous transmissions of the same data NAKed. One screening technique is based on an estimated round trip time of a message. Another alternate technique looks a flag in the NAK that synchronizes the sender and the receiver.

System and method for error recovery using NAKs

A method to adjust the burst transmission duration time, in a high speed digital wireless communication system, to provide sufficient time for the transmission of data when all the data is not available at the time of transmission. According to the method of the invention, after the burst transmission is begun, the burst is maintained active as additional data is selected within a known time period following the previous detected data packet and the detected data is appended to the active burst transmission. The invention further terminates the burst duration when no additional data is detected within the redefined time period following the previous detected data packet.

Method of dynamically adjusting the duration of a burst transmission in wireless communication systems

A method for allocating utilization of multiple carriers in a wideband CDMA transmission system first determines the carrier utilization/interference levels for each of the multiple carriers. Based on the carrier utilization/interference level, carrier assignments are allocated on an unequal basis. The allocation of the carrier assignment biases the selection of the carriers away from higher utilized/interfered carriers. An apparatus for implementing the method is also described.

Dynamic and smart spreading for wideband CDMA

Methods and apparatus for estimating mobile station location in a wireless communication system. At initiation of a call or a page response, a mobile station of the system sends an access request signal to a primary base station. The primary base station responds with an access acknowledgment which may be intentionally delayed such that the mo bile station increases its transmit power level. The primary base station then transmits a channel assignment message to the mobile station. The mobile station responds by transmitting a location signal in the form of a known user-specific traffic preamble at the higher transmit power level. The primary base station intentionally delays sending an acknowledgment of the preamble, such that the mobile station transmits the preamble for a longer period of time than it would otherwise. This additional transmission time allows the preamble to be detected accurately in the primary base station as well as in a number of other surrounding base stations in a manner suitable for generating path delay measurements. A primary location processor associated with the primary base station uses the path delay measurements from the primary and surrounding base stations to generate an estimate of mobile location. The mobile location estimation may be provided during an on-going call by the primary base station sending a fake handoff message to the mobile station directing it to handoff to the same base station and traffic channel but with a different power level and preamble length, or by the primary base station sending a predetermined location probe message directing the mobile station to transmit the traffic preamble with a desired power level and preamble length.

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

A method to dynamically assign data rates, for digital data transmission in wireless communication systems, which are just sufficient to meet the needs of the use is presented. The method monitors the data traffic and anticipates when the assigned data rate is inadequate to support the data traffic resulting in a loss of data or when the assigned data rate is more than necessary to support the data traffic and results in inefficient usage of system resources.

Method of queue length based burst management in wireless communication systems

The invention provides a novel burst duration assignment process that increases the performance and improves the throughput of communication systems. In particular, the invention provides an optimal burst duration assignment methodology such that resources are efficiently utilized and maximized in a communication system such as a code division multiple access (CDMA) system. According to the invention, burst duration is assigned based on channel fading fluctuation and user mobility in the communication system. In general, shorter burst duration is assigned to users with higher fading fluctuation and high mobility. Longer burst duration is assigned to users with lower fading fluctuation and low mobility. In a particular embodiment of the invention, the burst assignment is based on a function of duration versus fluctuation.

Burst duration assignment based on fading fluctuation and mobility in wireless communication systems

A base station assembles a frame including information bits at a vocoding rate for downlink transmission over a traffic channel as channel bits at a channel rate. The base station places at least one rate-indicating bit at a beginning of the frame for indicating the vocoding rate. The mobile station evaluates the downlink transmission with consideration of the vocoding rate indicated by the at least one rate-indicating bit. The mobile station can determine the vocoding rate by decoding the beginning of the frame to permit power control in less than one frame duration from initial receipt of the frame at the mobile station.

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Parsippany, NJ, United States of America

Wen-Yi Kuo