This is applied to any mobile supporting gsm or cdma or hspa or any other network. In order to perform cell selection and reselection in multirat multiradio access technology 2g, 3g and 4g networks, we use combination between priority and ranking based. The contents of the present document are subject to continuing work within the. Mobile will continuously make measurements on its neighboring cells as indicated by the ba list to initiate cell reselection if necessary. Prioritybased cell reselection qualcomm incorporated.
Jul 04, 2014 user description, gsm umts lte cell reselection and handover 4. It explains the rationales behind their differing mechanisms and implementations while exploring the advantages and limitations of each technology. So when you try to test or troubleshooting cell selection step, you have to prove from ue side log that cell detectionsearch procedure were successful and complete. Ue has completed the cell selection reselection process and has chosen a cell. The primary purpose of cell reselection, regardless of intrafrequency, interfrequency, or interrat nature, is to ensure that the ue camps on or connects to the best cell in terms of radio condition, e. Then, it will describe the cell reselection procedure, with main focus on the criteria for cell reselection triggering and cell ranking. Neighbor cell is of high priority and received signal powerquality level is better than thresholdhigh limit or. Only lte cells fulfilling the scriteria, that is cells with srxlev 0, are considered as candidates for cell reselection. Blacklisted cells are excluded from list of candidate cells for cell reselection. Rf planning and optimization in gsm and umts networks under the.
As an ofdma technology lte assumes small nominal guard band 10 %, excluding 1. After the ue accesses a gsm cell, the sgsn directly sends an iu release command message to the srnc, if the packet data protocol pdp context does not need to be transferred. The ue monitors system information and in most cases paging information. Once it finds the right cell it will start using the ba bcch allocation list transmitted by the bcch carrier for cell reselection, will be discussed later. Ue has completed the cell selectionreselection process and has chosen a cell. Intersystem cell reselection parameter optimization in.
The ipbased lte mobile network has a flat and much simpler structure comparing to the gsm. Intersystem cell reselection parameter optimization qualcomm. Click download or read online button to get from gsm to lte book now. Cell reselection for transitioning a user device from a macro cell to a small cell may be performed by comparing a first reselection candidate small cell and a second reselection candidate small cell based on reselection criteria, and selecting a final reselection candidate based on the comparison.
This situation arises when mobile station moves to new plmn area and hence it need to find suitable cell within the new plmn to camp on and secure access to the. Intersystem cell reselection parameter optimization in umts. Measurements on utran and eutran frequencies are triggered differently depending on if the frequencies have lower or higher priority than gsm. Nokia siemens networks lte 1800 mhz introducing lte with. User description, gsm umts lte cell reselection and handover. Cell selection and reselection schemes in multirat networks. We borrow cell selection and reselection criterion algorithm as measurement procedure. Select and monitor the indicated pich and pch of the cell according to information sent in system information.
However, only when specific criteria are fulfilled is the ue allowed to camp on that cell. If the ue finds a better cell, ue reselects it and camps on it. Rx levela rx levelb for 5 seconds is enough for a cell reselection if both cells are dcs, then it is same as 2 gsm cells. In order to reduce the number of unnecessary ue user equipment cell reselection in multirat multiradio access technology that consists of 2g, 3g and lte for energy saving, a new method on. Intersystem cell reselection between wcdma and gsm enables the user equipment in idle mode to choose a new cell of another system to camp on, thus providing service availability when wcdma. Long term evolution lte systems are the most popular mobile communication systems around the world for not only the higher access rate and lower latency but also the enhanced security and privacy scheme for users. In a recent study 6, intrafrequency cell reselection parameter settings have been optimized for standby time. The operator license can be shared highly efficiently between lte and gsm portions with the rf sharing solution. The mobile then will tune to the second strongest bcch carrier and subsequently does the same process over and over again until it finds the right cell. User equipment ue procedures in idle mode and procedures for cell reselection in connected mode.
This site is like a library, use search box in the widget to get ebook that you. The previous section described how initial cell selection will work and the difference between lte fdd and tdlte. Perform necessary measurements for the cell reselection. Training material umts cell selection and reselection. Cell re selection procedure is the process by which uemobile finds the suitable cell to camp on. These criteria for cell selection as well as cell reselection for lte are specified in 3. Lte network has priority 7 and the utran network has priority 3 from the utran network perspective. Intersystem cell reselection parameter optimization. Here in this document, we will only discuss intrafrequency cell reselection i. After camping on, ue monitors the system information to get the quality threshold and performs measurements for the cell reselection evaluation procedure. This mechanism, based onparameters provided by the network, is needed to camp on a good quality cell, and therefore achieve the desiredcall setupperformance. At least 5 measurement sample per neighboring cell is needed. Umts to gsm handover can be triggered by the ue speed estimation algorithm of the hcs. From gsm to lte download ebook pdf, epub, tuebl, mobi.
If more than one cell meets the cell reselection criteria above, the ue shall reselect the lte cell with the highest srxlev level among the cells meeting the criteria on the highest absolute priority layer. User description, gsm umts lte cell reselection and handover 4. Multiradio access technology 2g, 3g and 4g networks, we use combination between priority and. Load balancing optimization in lteltea cellular networks. The new cell is better ranked than the serving cell during a time interval treselection according to the r criteria. Here, the procedure for cell reselection at the serving cell is the same as in emm case 7. Pdf user description, gsmumtslte cell reselection and. An introduction to mobile networks and mobile broadband, 3 rd edition provides technical descriptions of the various wireless technologies currently in use. When mobile has been selected successfully the mobile now will start reselection tasks. Ue is in idle mode and has completed the cell selectionreselection process and has chosen a. Enhancement of the utra optimisation of the utran architecture to ensure the continued competitiveness of the 3gpp technologies for the future lte was the first and only technology recognized by the next generation mobile network alliance to meet its broad requirements target deployment in 2010. Technical specification ts initial planned release. When a suitable cell is found or if only an acceptable cell is found it camps on that cell and commence the cell reselection procedure.
How to perform priority based cell reselection from gsm, wcdma to lte network. Request pdf cell selection and reselection schemes in multirat networks in. How to perform priority based cell reselection from gsm, wcdma to lte network parameter settings and methodology. In a real life scenario it might be wise to set the thresholds lower if it is wanted to keep the ues in lte as long as possible. In case of reselection from a lower priority cell to higher priority cell the below condition should hold good for atleast the t reselection timer. Cell selection and reselection in lte ue teletopix. For gsm, the signal level of the gsm bcch carrier of each gsm neighbor cell. Cell selection and reselection schemes in multirat. More than 1 second has elapsed since the ue camped on the current serving cell. Gsm enables the user equipment in idle mode to choose a new cell of another system to camp on, thus. Ue is in idle mode and has completed the cell selection reselection process and has chosen a cell irrespective of plmn identity. A novel cell reselection method in the scenario of multirat.
Intrafrequency and equal priority interfrequency cell reselection criteria. Oct, 2015 in order to perform cell selection and reselection in multirat multiradio access technology 2g, 3g and 4g networks, we use combination between priority and ranking based. This is to let ue get connected to cell which has the best condition among all the cells to which the ue is allowed to camp on. According to some aspects, it is determined that serving gsm base 512 is not broadcasted lte neighbours and determines that ue510 can be locally, to contribute to the interrat cell reselection from conventional gsm cells 502 to lte cells, ue510 can for generation gsm to lte reselecting parameters with based on to lte cells 504 and 506 it is. Cell reselection is a kind of mechanism to change cell after ue is camped on a cell and stay in idle mode. Reselection procedure is triggered by ue when ue is in idle mode and finds the neighbor and serving cell received signal powerquality levels are satisfying the below conditions. Mar 21, 2017 2g to 4g lte cell reselection parameter setting in huawei network this post will tell you about parameter setting related cell reselection from 2g to 4g lte in huawei network. This site is like a library, use search box in the widget to get ebook that you want. The lte air interface is well scalable in terms of bandwidth. The pathloss criterion parameter c1 which is used for cell.
If more than one cell meets the cell reselection criteria above, the ue shall reselect the lte cell with the highest srxlev level among the cells meeting the criteria on. Specifically for reselection, treselection variance is utilized. Cell reselection procedure wcdma to gsm cell reselection. The cross reference between gsm, umts, 3gpp and etsi identities can be found under. System parameters that control cell reselection and the operators channel frequency preferences are. In the uncoordinated case it is 3gpp recommended practice that the center. User description, gsmumtslte cell reselection and handover 4. When the hierarchical cell structure hcs is used, the cells are divided into different layers on the basis of coverage. Cell reselection procedure is the process by which uemobile finds the suitable cell to camp on. Measurements for cell reselection to umts and lte based on priority. A novel cell reselection method in the scenario of multi. If you have new 4g network in your project and inter working system 2g to 4g will be set properly, this post will be useful for you.
Again, this time however the ue, after cell reselection, must perform a tau procedure before it camps on the new cell. The plmn knows the tracking area of the cell in which the registered ue is camped. A suitable cell is one for which the measured cell attributes satisfy the cell selection criteria. Wcdma 3g irat interrat handover principle and its parameters. User description, gsmumtslte cell reselection and handover. Lte must accommodate handover to and from other radio access technologies, such as gsmgprsedge. Cell search and cell selection in umts lte application note. According to statistics2, the most common english surname is smith, which corresponds to physical layer cell identity group 0.
In case of reselection from a lower priority cell to higher priority cell the below condition should hold good for atleast the treselection timer. Camped normally state overview in this state, the ue obtains normal service and performs the tasks as. The c2 criterion is used for cell ranking in the gsm cellreselection process. The ue should conduct some measurements to support this procedure. Typically, a marco cell has large coverage and low priority, whereas a micro cell has small coverage and high priority.
Intersystem cell reselection optimization in umts qualcomm. The ms shall perform measurement of higher priority frequencies once every 60 number of interrat frequencies of higher priority. Cell reselection procedures in lte lteencyclopedia. The nodeb sends a radio link failure indication message, because the ue shuts down transmission towards the wcdma cell after cell reselection to a gsm cell. Before you think of cell selection cell selection is the procedure that happens when cell detectionsearch procedure were successful and complete. The previous section described how initial cell selection will work and the difference between lte fdd and td lte. Cell selection cell reselection linkedin slideshare.
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