Open-loop power control enhancement for blind rescue channel operation

Abstract

A method and apparatus for determining an efficient and reliable power level for the MS's transmitter for reverse link communications during a rescue procedure to rescue dropped calls quickly and with a high success rate is disclosed. A mobile station's mean rescue transmission output power level is computed by first determining the mobile station's mean receive input power level when the mobile station transmits during a connection rescue procedure. This mean receive input power level is then adjusted using up to four parameters. These four variables include (1) a pre-rescue power delta, (2) a rescue interference delta, (3) a rescue delay compensation value, and (4) a pre-determined value.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application is a division of U.S. patent application Ser. No. 10 / 052,783 filed Jan. 18, 2002, which in turn claims priority from U.S. provisional patent application Ser. No. 60 / 262,689 entitled “Open-Loop Power Control Enhancement for Blind Rescue Channel Operation,” filed Jan. 19, 2001, both of which are related to U.S. utility application Ser. No. 09 / 978,974 entitled “Forward Link Based Rescue Channel Method and Apparatus for Telecommunication Systems,” filed Oct. 16, 2001, the contents of which are incorporated herein by reference for all purposes.BACKGROUND OF THE INVENTION [0002] 1. Field of the Invention [0003] The present invention relates, generally, to communication network management and, in one embodiment, to a method and apparatus for utilizing open-loop power control to control the transmit power of a mobile station transmitter during a connection rescue procedure. [0004] 2. Description of Related Art Introduction [000...

AI Technical Summary

Benefits of technology

[0056] The MS may also add a rescue delay compensation value to the MS's mean rescue transmission output power level to account for the increased uncertainty in computing a new mean rescue transmission output power level as the time t between the start of the fade and start of the MS's transmission increases. Generally, as t increases, more uncertainty is introduced in computing a new MS transmit power level and the more desirable it may be to boost the initi

Problems solved by technology

Dropped connections can range from being a nuisance to devastating for cellular telephone users.

For example, a dropped emergency 911 connection can be critical or even fatal.

Dropped connections can create consumer frustration significant enough to cause the consumer to change service providers.

However, because there are practical limitations on the number of MSs that can be simultaneously paged using one paging channel, some BSs may employ multiple paging channels.

The practical limit of signal reception depends on the channel conditions and interference level.

Types of interference include those generated when the signal is propagated through a multi-path channel, signals transmitted to and from other users in the same or other cell sites, as well as self-interference or noise generated at the device or MS.

However, noise and interference in the field may require error correction to determine what was actually transmitted.

When the data is combined through maximum ratio combining or other similar combining algorithms, the data from a strong channel may be weighted more heavily than data from a weak channel, which is likely to have more errors.

It should be noted, however, that the new active set may not always exactly comply with the MS's request, because the network may have BS resource considerations to deal with.

Soft handoff allows a MS to maintain communication with one or more BSs (sectors) simultaneously while the condition of any one of these links is not sufficient

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