| Method and apparatus for utilizing a directional beam antenna in a wireless transmit/receive unit -> Monitor Keywords |
|
|
 
Method and apparatus for utilizing a directional beam antenna in a wireless transmit/receive unitMethod and apparatus for utilizing a directional beam antenna in a wireless transmit/receive unit description/claimsThe Patent Description & Claims data below is from USPTO Patent Application 20090111381, Method and apparatus for utilizing a directional beam antenna in a wireless transmit/receive unit. Brief Patent Description - Full Patent Description - Patent Application Claims
This application is a continuation of U.S. patent application Ser. No. 10/997,618, filed Nov. 24, 2004, now U.S. Pat. No.7,460,834, which claims the benefit of U.S. Provisional Application Nos. 60/524,579 filed Nov. 24, 2003, and 60/524,471 filed Nov. 24, 2003, which are incorporated by reference as if fully set forth. The present invention is related to a wireless communication system. More particularly, the present invention is a method and apparatus for utilizing a switched beam directional antenna in a wireless transmit/receive unit (WTRU) operating in a cellular network. The present invention is applicable to any wireless communication system including, but not limited to, Global System For Mobile Communications (GSM), General Packet Radio System (GPRS), and Enhanced Data Rates For GSM Evolution (EDGE). One of the most important areas in cellular technology development is the exploration of ways to improve the capacity of the system. Spectral efficiency and power consumption in mobile systems are forcing wireless communications designers to explore new areas in the technology that will offer capacity relief. One of these new areas being explored is the use of directional beam antennas to improve the link margin of the forward and reverse links between a base station and a WTRU. The increased gain of the directional antenna over the typical omni-directional antenna provides increased received signal level at the WTRU receiver allowing the base station to transmit at a lower power level. This allows more users to be simultaneously active, (i.e., more capacity), and lowers the interference seen by WTRUs in adjacent cells. Directivity of the antenna in a WTRU can also provide a reduction in the interference level from signals received from adjacent base stations. The reverse link from the WTRU to the base station enjoys the same link margin improvement, thereby allowing the WTRU to transmit at lower power level. This reduces the interference seen at base stations of adjacent cells and can lengthen the battery life at the WTRU. The use of a directional antenna at a WTRU requires decisive reference to the signal level measurements on each of the directional beams in order to select the best directional mode of the antenna. In a mobile communication network, the WTRU must continually monitor the received signal level in each of the directional modes and periodically reselect the best directional mode to accommodate environment changes and movement of the WTRU. In a GSM network where a TDMA scheme is employed to accommodate multiple users, inactive timeslots, (i.e., where the WTRU is not required to transmit or receive), can be used to make these measurements. However, the signal level received at the WTRU constantly changes due to multi-path propagation. Thus, measuring a higher received signal level in one direction versus another at a given time may not result in the best directional beam selection. The present invention is a method and apparatus for steering a switched beam directional antenna employed at a WTRU operating in a wireless system, including, but not limited to, GSM/GPRS/EDGE type cellular systems. The WTRU measures the received signal from the serving base station in each of the directional modes of the switched beam antenna and selects the direction having the best signal. The measurements are made during inactive timeslots where the WTRU is not required to transmit or receive. Typically, the WTRU is assigned one timeslot to transmit and one timeslot to receive of the eight TDMA slots available in the GSM system, leaving six inactive timeslots. The signal measurement in each directional mode can be formed from the total received signal power averaged over the timeslot, (hereafter called the received signal strength indication or RSSI), received on the BCCH from the serving base station. It can also be formed from an average over a portion of the timeslot. This allows multiple beams to be measured within the same timeslot, thereby reducing the time required to develop a beam selection decision. Alternatively, the signal quality or carrier-to-interference ratio (CIR) of the signal received from different directional modes of the antenna may be measured using the midamble of the GSM burst waveform. This technique would be applicable when measuring traffic channel slots that can also contain interference from adjacent base stations. The midamble contains a known data sequence used to discriminate between the desired signal, (i.e., the serving base station), and interfering signals received from other base stations. In general, the beam selection decision does not rely on a single set of measurements because of signal level fluctuations due to multi-path fading. Averaging the measurements from each direction prior to selecting the best direction is an effective technique. Alternately, when measuring several beams within the same timeslot, the signal level differences seen timeslot-by-timeslot can be used to form the beam selection decision. When performing received power measurements of neighbor cells for handoff decisions, the WTRU would be restricted to the omni-directional antenna. This provides consistent relative signal strength measurements of neighboring cells that may appear at different angles of arrival. However, if the WTRU has spare processing power to collect multi-beam measurements on neighbor cells, handoff to a directional beam may be considered. A more detailed understanding of the invention may be had from the following description of a preferred embodiment, given by way of example and to be understood in conjunction with the accompanying drawings wherein: Continue reading about Method and apparatus for utilizing a directional beam antenna in a wireless transmit/receive unit... Full patent description for Method and apparatus for utilizing a directional beam antenna in a wireless transmit/receive unit Brief Patent Description - Full Patent Description - Patent Application Claims Click on the above for other options relating to this Method and apparatus for utilizing a directional beam antenna in a wireless transmit/receive unit patent application. ###  How KEYWORD MONITOR works... a FREE service from FreshPatents1. Sign up (takes 30 seconds). 2. Fill in the keywords to be monitored. 3. Each week you receive an email with patent applications related to your keywords. Start now! - Receive info on patent apps like Method and apparatus for utilizing a directional beam antenna in a wireless transmit/receive unit or other areas of interest. ### Previous Patent Application: Apparatus and method for connecting wireless devices Next Patent Application: Methods for signaling and determining the time of the beginning of a measurement time interval, communication device and communication network element Industry Class: Telecommunications ### FreshPatents.com Support Thank you for viewing the Method and apparatus for utilizing a directional beam antenna in a wireless transmit/receive unit patent info. IP-related news and info Results in 2.64338 seconds Other interesting Feshpatents.com categories: Canon USA , Celera Genomics , Cephalon, Inc. , Cingular Wireless , Clorox , Colgate-Palmolive , Corning , Cymer , paws |
 * Protect your Inventions * US Patent Office filing 
PATENT INFO |
|
