US20060014538A1 - Frequency quality criteria for inter-frequency handover in a TD-CDMA communication system - Google Patents

Frequency quality criteria for inter-frequency handover in a TD-CDMA communication system Download PDF

Info

Publication number
US20060014538A1
US20060014538A1 US10/891,829 US89182904A US2006014538A1 US 20060014538 A1 US20060014538 A1 US 20060014538A1 US 89182904 A US89182904 A US 89182904A US 2006014538 A1 US2006014538 A1 US 2006014538A1
Authority
US
United States
Prior art keywords
decision metric
capacity
user equipment
related
cell
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
US10/891,829
Inventor
Zhu Yuan
Original Assignee
Zhu Yuan
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Zhu Yuan filed Critical Zhu Yuan
Priority to US10/891,829 priority Critical patent/US20060014538A1/en
Publication of US20060014538A1 publication Critical patent/US20060014538A1/en
Application status is Abandoned legal-status Critical

Links

Images

Classifications

    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04WWIRELESS COMMUNICATION NETWORKS
    • H04W36/00Hand-off or reselection arrangements
    • H04W36/14Reselecting a network or an air interface
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04WWIRELESS COMMUNICATION NETWORKS
    • H04W36/00Hand-off or reselection arrangements
    • H04W36/16Performing reselection for specific purposes
    • H04W36/22Performing reselection for specific purposes for handling the traffic

Abstract

A method for determining whether to perform IFHO (inter-frequency handover) of a UF apparatus from one cell to another and from one carrier frequency to another in a TD-CDMA telecommunications network (including e.g. a TD-SCDMA network)—based separately on coverage and capacity, using one decision metric for coverage (e.g. based on received signal code power for each candidate cell and each candidate carrier frequency) and a different decision metric for capacity (e.g. based on a quantity proportional to the received signal code power and inversely proportional to the difference between a received signal strength indicator and the received signal code power). Corresponding equipment and a computer program product is also provided. In deciding whether IFHO is needed based on capacity, a threshold for received signal code power may be used in addition to the metric for capacity.

Description

    TECHNICAL FIELD
  • The present invention pertains to the field of wireless communication. More particularly, the present invention pertains to criteria used in inter-frequency handover in a cellular communication system.
  • BACKGROUND ART
  • TD-SCDMA (Time Division-Synchronized Code Division Multiple Access), also known as UTRA (Universal mobile telecommunications system (UMTS) Terrestrial Radio Access) TDD (time division duplex) 1.28 Mcps option, is a so-called 3G (third generation) wireless communication system that is supposed to be used for example in China, possibly along with two other 3G technologies—UTRA FDD version of WCDMA (Wideband CDMA) and CDMA2000.
  • TD-SCDMA uses both TDMA (Time Division Multiple Access) and CDMA as multiple access methods, which means there are several possible slots for each transmitting direction on a single carrier, and in each slot one or more users, separated by orthogonal codes, can transmit or receive data simultaneously, one user can even occupy more than one timeslot during multi-slot mode.
  • Since TD-SCDMA uses a 1.6 MHz bandwidth, it has a low single-carrier capacity. Thus, a TD-SCDMA is usually implemented (by a network operator) using more than one carrier. Even so, to prevent a communication link from deteriorating because of over-capacity, inter-frequency handover (IFHO) must be performed relatively frequently. IFHO is also performed because of coverage, i.e. because of a user equipment (UE) (a cellular communication device, e.g. a cellular telephone) moving beyond the coverage of a network service access point (SAP), e.g. a so-called Node B.
  • TD-SCDMA uses hard handover (from one SAP to another, without a time interval during which the UE is in communication with both) instead of soft handover (includes a time interval during which the UE is in communication with two or more SAPs) to make the UE always connect to a single best cell. The quantity used to define how good a cell is, per the prior art, P-CCPCH RSCP (Primary-Common Control Physical CHannel Received Signal Code Power). After passing the cell-planning phase, the coverage area is decided by the antenna down tilt, gain map and Tx (transmit) power of P-CCPCH. The Tx power of P-CCPCH changes only rarely. Hence the coverage area of a cell also rarely changes. The cell-planning phase ensures that the best cell's P-CCPCH RSCP in the whole service area is above an acceptable threshold.
  • Based on where the UE is located in a service area, the P-CCPCH RSCP of all detectable cells would reflect the admission cost (power increase of the whole network for both directions) of the UE in that location. Estimation cost in slot 1 to slot 6 from measurement of slot 0, which is the slot used by P-CCPCH, would not be very accurate, but it would be sufficient on an average basis without information about other slots in the location. The potential downlink power increase after admitting the UE in the specific location is decided by both the path loss from the serving cell and the path loss from any interfering cells. The serving cell's P-CCPCH RSCP would only directly reflect the path loss from the serving cell, but it would also indirectly reflect the path loss from interfering cells. In other words, the serving cell's P-CCPCH RSCP is affected by and so indicates interference from interfering cells. So selecting a cell having the best P-CCPCH RSCP in one carrier as the serving cell is a UE's best choice for intra-frequency handover.
  • However, for inter-frequency handover cell quality criteria, selecting a cell having the best P-CCPCH RSCP is not always the best choice since a good P-CCPCH RSCP does not necessarily indicate low interference at slot 0 compared with other cells.
  • Thus, what is needed is a new decision algorithm by which to select a best cell during inter-frequency handover based on minimizing admission cost.
  • DISCLOSURE OF THE INVENTION
  • Accordingly, in a first aspect of the invention, a method (for use by e.g. a network element of a wireless communication system) is provided comprising: a step of selecting either a decision metric related to coverage or a decision metric related to capacity as a basis for deciding whether to perform an inter-frequency handoff of a user equipment apparatus; and a step of determining whether to perform the interfrequency handover using the selected decision metric.
  • In accord with the invention, the decision metric related to capacity may vary in inverse proportion to the difference between a received signal strength indicator for a cell and a carrier frequency and the received signal code power for the cell and the carrier frequency, or in inverse proportion to quantities algebraically related so as to behave in a similar way.
  • Also in accord with the invention, the decision metric related to capacity may be the received signal code power for a cell and a carrier frequency divided by the difference between a received signal strength indicator for a cell and a carrier frequency and the received signal code power for the cell and the carrier frequency, or may be a quantity algebraically related so as to behave in a similar way.
  • In accord with the first aspect of the invention, the step of determining whether to perform an interfrequency handover may be based not only on the decision metric related to capacity, but also on a threshold for received signal code power.
  • In a second aspect of the invention, a computer program product is provided comprising a computer readable storage structure embodying computer program code thereon for execution by a computer processor, where the computer program code comprises instructions for performing a method according to a first aspect of the invention.
  • In a third aspect of the invention, a network element is provided, comprising: means for selecting either a decision metric related to coverage or a decision metric related to capacity as a basis for deciding whether to perform an inter-frequency handoff of a user equipment apparatus; and means for determining whether to perform the interfrequency handover using the selected decision metric.
  • In a fourth aspect of the invention, a method (for use e.g. by a user equipment apparatus) is provided, comprising: a step in which a user equipment apparatus receives an indication that an inter-frequency measurement is to be performed and that an indicated decision metric is to be used in ranking cells and frequencies; and a step in which the user equipment apparatus performs an interfrequency measurement and ranks the results for different cells and frequencies according to the decision metric; wherein the decision metric can be indicated to be either a decision metric related to capacity or a decision metric related to coverage.
  • In a fifth aspect of the invention, a computer program product is provided, comprising a computer readable storage structure embodying computer program code thereon for execution by a computer processor, where the computer program code comprises instructions for performing a method according to the fourth aspect of the invention.
  • In a sixth aspect of the invention, a user equipment apparatus is provided, comprising: means by which the user equipment apparatus receives an indication that an inter-frequency measurement is to be performed and that an indicated decision metric is to be used in ranking cells and frequencies; and means by which the user equipment apparatus performs an interfrequency measurement and ranks the results for different cells and frequencies according to the decision metric; wherein the decision metric can be either a decision metric related to capacity or a decision metric related to coverage.
  • In a seventh aspect of the invention, a system is provided, comprising: a network element according to the third aspect of the invention, and a user equipment apparatus coupled to the network element via a radio link. The user equipment apparatus may be according to the sixth aspect of the invention. The radio link may be e.g. any kind of time division code division multiple access radio link including a time division synchronized code division multiple access radio link, or a time division duplex radio link.
  • BRIEF DESCRIPTION OF THE DRAWINGS
  • The above and other objects, features and advantages of the invention will become apparent from a consideration of the subsequent detailed description presented in connection with accompanying drawings, in which:
  • FIG. 1 is a block diagram showing a system of a type for which the invention can be used, and showing a network entity—and in particular a radio network controller—including means for performing a method according to the invention.
  • FIG. 2 is a flow chart of a method according to the invention (for execution by a network entity, such as a radio network controller).
  • FIG. 3 is a flow chart showing operation of a UE according to the invention.
  • DETAILED DESCRIPTION OF THE INVENTION
  • According to the invention, the IFHO algorithm for TD-SCDMA is modified so as to include a frequency criteria or metric for two different causes of IFHO: one for coverage-caused link deterioration (i.e. for the case that a UE moves outside of the coverage area of a SAP) and the other for over-capacity. For coverage-caused IFHO, the IFHO metric can be the same as in the prior art, namely:
    M (IFHO-coverage) =P RSC,   (1)
    where PRSC is P-CCPCH RSCP (for a particular cell i, not made express in the above, and for a particular frequency j, also not made express), i.e. the received signal code power for P-CCPCH (for a cell i). For over-capacity, the IFHO metric can be:
    M (IFHO-capacity) =P RSC/(I RSS −P RSC),   (2)
    (again for a particular cell i, not made express, and for a particular frequency j, also not made express) where IRSS=UTRA Carrier RSSI (Received Signal Strength Indicator), which is used here to indicate the wideband power of slot 0. Other metrics for the IFHO capacity metric are possible according to the invention, but advantageously, any IFHO capacity metric exhibits the same general behavior as M(IFHO-capacity) given by eq. (2) by virtue of being algebraically related. Thus, for example, the invention includes as possible formulae for M(IFHO-capacity) any of the following:
    [PRSC/(IRSS−PRSC)]2,
    PRSC/(IRSS−PRSC)
    PRSC/(IRSS−PRSC)2,
    PRSC/(IRSS−PRSC 2),
    log {PRSC/(IRSS−PRSC)}, or
    PRSC/(IRSS−PRSC+δ),
    where δ is a small constant for regulating the behavior of M(IFHO-capacity) when IRSS−PRSC is small. Other formulae are of course also possible. According to the invention, any formula for M(IFHO-capacity) takes into account both PRSC as well as how close PRSC is to IRSS.
  • Thus, according to the invention, the decision algorithm used to decide whether to perform IFHO tests for both over-capacity and coverage based link deterioration, and performs IFHO in case either test indicates that IFHO should be performed. For the capacity test, the best cell i (and for a particular frequency j)—and so the cell to which handover would be performed—can be the cell having the highest M(IFHO-capacity) and also having an acceptable P-CCPCH RSCP, i.e.: Max i , j { M i , j ( IFHO - capacity ) } , ( 3 )
    where i indicates a neighboring cell and j the frequency, and
    PRSC i,j>PRSC threshold   (4)
    where PRSC threshold is a P-CCPCH threshold designed to be several dB (deciBel) above a minimum required (e.g. by an accepted standard) P-CCPCH value. The threshold requirement given by eq. (4) is to avoid link deterioration because of coverage reason soon after a UE is handed over to a cell because of the limit on capacity in the cell from which the UE is handed over.
  • For an IFHO decision because of coverage, the best cell can be the cell having highest P-CCPCH RSCP, as in the prior art, or having the largest M(IFHO-coverage) value for any IFHO coverage metric (typically having the same general behavior as the quantity P-CCPCH RSCP).
  • A UE is advantageously (although not necessarily) adapted for use according to the invention by including in it functionality for ranking cells according to the both kinds of metrics described above. According to the prior art (3GPP TS 25.311, section 10.3.7.44), the measurement report sent from the UE to the RNC should rank cells from best to worst according to RSCP, as measured by the coverage metric, and so a UE according to the invention should include functionality for ranking cells in two ways: according to the coverage metric for coverage-caused IFHO and according to the capacity metric for capacity-caused IFHO.
  • The RNC advantageously then commands a UE to perform a frequency quality measurement and provide results either according to a capacity metric or a coverage metric, as described above. The downlink Ec/No according to the prior art (3GPP TS 25.311, section 14.2.0a) can be re-interpreted to indicate to the UE that it is to use a capacity metric as described above (e.g. P-CCPCH RSCP/UTRA Carrier RSSI (slot 0)) for the UTRA TDD 1.28 Mcps option. With such a change, when the measurement quantity (as indicated by FE-TDD where FE is the Frequency Quality Estimate Quantity) is set to primaryCCPCH-Ec-NO (as opposed to RSCP or path loss), the UE should use the capacity metric. When it is set to RSCP, the UE should use the coverage metric.
  • In other embodiments, the RNC receives from the UE the raw measurement results and itself performs the rankings according to either a coverage metric or a capacity metric. In such embodiments, the UE need not be at all changed to be used with the invention.
  • A decision algorithm according to the invention advantageously resides in the RRM/HC (Radio Resource Management/Handoff Control) of the RNC (Radio Network Controller). The quantities P-CCPCH RSCP and UTRA Carrier RSSI are already supported in the RRC (Radio Resource Control) measurement report message specified by 3GPP TS 25.331, v500. Page 841 of 3GPP TS 25.331 v500 gives the following as a frequency quality metric for TDD (Time Division Duplex) used in determining whether to perform IFHO:
    Q i,j=10·Log(M i,j)+O i,j   (5)
    where Qi,j is the estimated quality of cell i on frequency j, Mi,j is the measurement result for Primary CCPCH RSCP of cell i on frequency j expressed in mW, and Oi,j is the cell individual offset (set by the information element (IE) called “cell individual offset”) of the currently evaluated cell i on frequency j. The invention can be implemented to use the frequency quality metric given by eq. (5), but using two different Mi,j: Mi,j (IFHO-coverage) for coverage, and Mi,j (IFHO-capacity) for capacity, as explained above.
  • Thus, and now referring to FIG. 1, according to the invention, a UE 11 is physically located so as to be able to establish wireless communication with a radio network controller 14 a and on to a core network 16 (and ultimately another communication terminal or server, not shown) via a radio link to a SAP 12 a having a cell i and using a carrier frequency j from among the various carrier frequencies 1, . . . , j, . . . , N available for use with the SAP 12 a. An IFHO (hard handover, in which the carrier frequency changes) can be performed to another SAP 12 b-d as needed because of deterioration in the radio link due to either the UE having moved outside of the cell i (or having moved to a location where coverage from another of the SAPs 12 b-d is superior) or because of too many users in the cell i. In case of an IFHO, the UE can be handed over to another of the SAPs 12 b-d (each providing a different cell than cell i) and the carrier frequency is changed to another of the available carrier frequencies (depending on the SAP selected as the serving SAP), according to the invention as described above, i.e. using a metric for coverage and a metric for capacity.
  • As indicated above, a radio access network (the RNCs and SAPs) can have several different carriers to use, and can use some in one cell and some (the same or different) in others of the cells. Thus, the carrier frequencies for two cells may overlap partially, wholly, or not at all. Typically, though, at least one carrier frequency is used in all of the cells in order to provide for continuous coverage in the service area, and other carrier frequencies are used in addition only where demand is high. (Note also that the coverage areas of the different carrier frequencies for a cell need not be the same within the cell.)
  • Referring now also to FIG. 2, the process of deciding whether to perform IFHO—and if so to what cell and carrier frequency—is shown as including a first step 21 in which the RNC obtains from UE measurement results needed to decide whether to perform IFHO (for example, using messaging according to the prior art). In a next step 22, the RNC determines whether to perform IFHO based on coverage, and if so, to what cell and what frequency, using the measurement results provided by the UE. This determination can be made as in the prior art, e.g. as set out in 3GPP TS 25.331, v.500 (see page 841). If the outcome of the test indicates that IFHO should be performed, then in a next step 23, the IFHO is performed so as to possibly hand off the UE 11 to another of the SAPs 12 b-d, and so as to change the carrier frequency. If the measurements instead indicate that IFHO is not needed based on coverage, then in a next step 24, the RNC determines whether to perform IFHO based on capacity, and if so, to what cell and what frequency, using e.g. eqs. (3) and (4), but at any rate using a different metric than that used for determining whether IFHO is needed based on coverage. If the measurements indicate that IFHO is needed based on capacity, then the step 23 of performing IFHO is performed. Clearly, the determining of whether to perform IFHO based on coverage may be performed either before or after the determining of whether to perform IFHO based on capacity, and the order is advantageously tailored to each RNC 14 a-b.
  • As explained above, the invention provides a method and it also provides corresponding equipment consisting of various modules providing the functionality for performing the steps of the method. The modules may be implemented as hardware, or may be implemented as software or firmware for execution by a processor. In particular, in the case of firmware or software, the invention can be provided as a computer program product including a computer readable storage structure embodying computer program code—i.e. the software or firmware—thereon for execution by a computer processor.
  • Referring now to FIG. 3, in embodiments in which the UE itself performs rank orderings of cells and frequencies according to a decision metric, the invention provides a method according to which the UE is operative and including a first step 31 in which the UE receives from the RNC a command to perform an inter-frequency measurement and to then rank cells and frequencies based on an indicated decision metric that can be either coverage-related or capacity-related. In a next step 32, the UE performs the inter-frequency measurement, ranks the cells and frequencies based on the indicated decision metric, and reports the ranking to the RNC.
  • As indicated above, the invention is especially advantageous in case of TD-SCDMA. More generally, the invention is of use in any TD-CDMA (Time Division-Code Division Multiple Access) communication system, and so e.g. can also be used for the UTRA TDD (time Division Duplex) 3.84 Mcps option.
  • Advantages of the invention are that it takes into account the possible cite density differences of different frequencies, that the capacity caused IFHO tends to select a carrier in which cites are sparse, and that since MUD can cancel most of the intra-cell interference, the single cell capacity of sparse cites is much larger than that of a continuous coverage carrier. Further, the intra-frequency handover algorithm is unaffected by the invention, and also the measurement control and measurement report in inter-frequency measurement need not change.
  • It is to be understood that the above-described arrangements are only illustrative of the application of the principles of the present invention. Numerous modifications and alternative arrangements may be devised by those skilled in the art without departing from the scope of the present invention, and the appended claims are intended to cover such modifications and arrangements.

Claims (16)

1. A method, comprising:
a step of selecting either a decision metric related to coverage or a decision metric related to capacity as a basis for deciding whether to perform an inter-frequency handoff of a user equipment apparatus; and
a step of determining whether to perform the interfrequency handover using the selected decision metric.
2. A method as in claim 1, wherein the decision metric related to capacity varies in inverse proportion to the difference between a received signal strength indicator for a cell and a carrier frequency and the received signal code power for the cell and the carrier frequency, or in inverse proportion to quantities algebraically related so as to behave in a similar way.
3. A method as in claim 1, wherein the decision metric related to capacity is the received signal code power for a cell and a carrier frequency divided by the difference between a received signal strength indicator for a cell and a carrier frequency and the received signal code power for the cell and the carrier frequency, or is a quantity algebraically related so as to behave in a similar way.
4. A method as in claim 1, wherein the step of determining whether to perform an interfrequency handover based on capacity is based not only on the decision metric related to capacity, but also on a threshold for received signal code power.
5. A computer program product comprising a computer readable storage structure embodying computer program code thereon for execution by a computer processor, wherein said computer program code comprises instructions for performing a method including:
a step of selecting either a decision metric related to coverage or a decision metric related to capacity as a basis for deciding whether to perform an inter-frequency handoff of a user equipment apparatus; and
a step of determining whether to perform the interfrequency handover using the selected decision metric; and
wherein the decision metric related to capacity differs from the decision metric related to coverage.
6. A network element, comprising:
means for selecting either a decision metric related to coverage or a decision metric related to capacity as a basis for deciding whether to perform an inter-frequency handoff of a user equipment apparatus; and
means for determining whether to perform the interfrequency handover using the selected decision metric.
7. A method, comprising:
a step in which a user equipment apparatus receives an indication that an inter-frequency measurement is to be performed and that an indicated decision metric is to be used in ranking cells and frequencies; and
a step in which the user equipment apparatus performs an interfrequency measurement and ranks the results for different cells and frequencies according to the decision metric;
wherein the decision metric can be indicated to be either a decision metric related to capacity or a decision metric related to coverage.
8. A method as in claim 7, wherein the decision metric related to capacity varies in inverse proportion to the difference between a received signal strength indicator for a cell and a carrier frequency and the received signal code power for the cell and the carrier frequency, or in inverse proportion to quantities algebraically related so as to behave in a similar way.
9. A computer program product comprising a computer readable storage structure embodying computer program code thereon for execution by a computer processor, wherein said computer program code comprises instructions for performing a method including:
a step in which a user equipment apparatus receives an indication that an inter-frequency measurement is to be performed and that an indicated decision metric is to be used in ranking cells and frequencies; and
a step in which the user equipment apparatus performs an interfrequency measurement and ranks the results for different cells and frequencies according to the decision metric;
wherein the decision metric can be indicated to be either a decision metric related to capacity or a decision metric related to coverage.
10. A user equipment apparatus, comprising:
means by which the user equipment apparatus receives an indication that an inter-frequency measurement is to be performed and that an indicated decision metric is to be used in ranking cells and frequencies; and
means by which the user equipment apparatus performs an interfrequency measurement and ranks the results for different cells and frequencies according to the decision metric;
wherein the decision metric can be either a decision metric related to capacity or a decision metric related to coverage.
11. A user equipment apparatus as in claim 10, wherein the decision metric related to capacity varies in inverse proportion to the difference between a received signal strength indicator for a cell and a carrier frequency and the received signal code power for the cell and the carrier frequency, or in inverse proportion to quantities algebraically related so as to behave in a similar way.
12. A system, comprising: a network element as in claim 6, and a user equipment apparatus coupled to the network element via a radio link.
13. A system as in claim 12, wherein the user equipment apparatus comprises:
means by which the user equipment apparatus receives an indication that an inter-frequency measurement is to be performed and that an indicated decision metric is to be used in ranking cells and frequencies; and
means by which the user equipment apparatus performs an interfrequency measurement and ranks the results for different cells and frequencies according to the decision metric;
wherein the decision metric can be either the decision metric related to capacity or the decision metric related to coverage.
14. A system as in claim 12, wherein the radio link is a time division code division multiple access radio link.
15. A system as in claim 12, wherein the radio link is a time division synchronized code division multiple access radio link.
16. A system as in claim 12, wherein the radio link is a time division duplex radio link.
US10/891,829 2004-07-14 2004-07-14 Frequency quality criteria for inter-frequency handover in a TD-CDMA communication system Abandoned US20060014538A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US10/891,829 US20060014538A1 (en) 2004-07-14 2004-07-14 Frequency quality criteria for inter-frequency handover in a TD-CDMA communication system

Applications Claiming Priority (7)

Application Number Priority Date Filing Date Title
US10/891,829 US20060014538A1 (en) 2004-07-14 2004-07-14 Frequency quality criteria for inter-frequency handover in a TD-CDMA communication system
CN 200580023608 CN1985540B (en) 2004-07-14 2005-05-25 Method and device for handover in TD-CDMA cellular communication
KR1020077003505A KR100894145B1 (en) 2004-07-14 2005-05-25 Frequency quality criteria for handover in TD-CDMA cellular communication
PCT/IB2005/001429 WO2006008591A1 (en) 2004-07-14 2005-05-25 Frequency quality criteria for handover in td-cdma cellular communication
JP2007520907A JP4681609B2 (en) 2004-07-14 2005-05-25 Method, storage medium, network element, user equipment for handover in TD-CDMA cellular communication
US11/631,497 US8190157B2 (en) 2004-07-14 2005-05-25 Frequency quality criteria for inter-frequency handover in a TD-CDMA communication system
US13/451,892 US8520640B2 (en) 2004-07-14 2012-04-20 Frequency quality criteria for inter-frequency handover in a TD-CDMA communication system

Related Child Applications (4)

Application Number Title Priority Date Filing Date
US11631497 Continuation-In-Part
US11/631,497 Continuation-In-Part US8190157B2 (en) 2004-07-14 2005-05-25 Frequency quality criteria for inter-frequency handover in a TD-CDMA communication system
PCT/IB2005/001429 Continuation-In-Part WO2006008591A1 (en) 2004-07-14 2005-05-25 Frequency quality criteria for handover in td-cdma cellular communication
US12/631,497 Continuation-In-Part US8728555B1 (en) 2009-12-04 2009-12-04 Apparatus and method for searing, branding, and cooking

Publications (1)

Publication Number Publication Date
US20060014538A1 true US20060014538A1 (en) 2006-01-19

Family

ID=35600114

Family Applications (3)

Application Number Title Priority Date Filing Date
US10/891,829 Abandoned US20060014538A1 (en) 2004-07-14 2004-07-14 Frequency quality criteria for inter-frequency handover in a TD-CDMA communication system
US11/631,497 Active 2026-11-25 US8190157B2 (en) 2004-07-14 2005-05-25 Frequency quality criteria for inter-frequency handover in a TD-CDMA communication system
US13/451,892 Expired - Fee Related US8520640B2 (en) 2004-07-14 2012-04-20 Frequency quality criteria for inter-frequency handover in a TD-CDMA communication system

Family Applications After (2)

Application Number Title Priority Date Filing Date
US11/631,497 Active 2026-11-25 US8190157B2 (en) 2004-07-14 2005-05-25 Frequency quality criteria for inter-frequency handover in a TD-CDMA communication system
US13/451,892 Expired - Fee Related US8520640B2 (en) 2004-07-14 2012-04-20 Frequency quality criteria for inter-frequency handover in a TD-CDMA communication system

Country Status (5)

Country Link
US (3) US20060014538A1 (en)
JP (1) JP4681609B2 (en)
KR (1) KR100894145B1 (en)
CN (1) CN1985540B (en)
WO (1) WO2006008591A1 (en)

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20080014941A1 (en) * 2006-07-17 2008-01-17 Amer Catovic Methods and apparatus for soft-decision based inter-radio access technology handover triggering
US20080146231A1 (en) * 2006-10-27 2008-06-19 Nokia Corporation Method and apparatus for handover measurement
US20080186919A1 (en) * 2006-10-30 2008-08-07 Nokia Corporation Apparatus, method and computer program product providing extended measurement control signal for handoff measurement under interference coordination
US20080227074A1 (en) * 2007-03-13 2008-09-18 Byron Johnson Correlated electronic notebook and method of doing the same
US20090131053A1 (en) * 2005-04-29 2009-05-21 Telefonaktiebolaget Lm Ericsson (Publ) Internetworking of Cellular Radio Networks and Wireless Data Networks
US20090149170A1 (en) * 2005-10-21 2009-06-11 Muhammad Ali Kazmi Apparatus and method for measurement reporting in a cellular telecommunications system
US20100248737A1 (en) * 2009-03-31 2010-09-30 Futurewei Technologies, Inc. System and Method for Interference Mitigation in a Wireless Communications System
US20100254353A1 (en) * 2006-04-25 2010-10-07 Qualcomm Incorporated Polarization reuse and beam-forming techniques for aeronautical broadband systems
EP2247155A1 (en) * 2008-01-23 2010-11-03 Fujitsu Limited Moble communication system
WO2011140399A1 (en) * 2010-05-06 2011-11-10 Qualcomm Incorporated Signal measurement in td-scdma multicarrier systems using downlink synchronization codes
US20120230295A1 (en) * 2009-11-10 2012-09-13 Qualcomm Incorporated Method and Apparatus to Support HSDPA ACK/CQI Operation During Baton Handover in TD-SCDMA Systems
US20130189971A1 (en) * 2012-01-24 2013-07-25 Renesas Mobile Corporation Modified Measurement Procedures for User Equipments
US20160302109A1 (en) * 2015-04-10 2016-10-13 Telefonaktiebolaget Lm Ericsson (Publ) System, method, and apparatus for preventing offload return
WO2019068628A1 (en) * 2017-10-02 2019-04-11 Telefonaktiebolaget Lm Ericsson (Publ) Improved inter-frequency search order

Families Citing this family (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101626622A (en) * 2004-07-27 2010-01-13 日本电气株式会社 Uplink line radio resource control method, base station device, and radio network control device
WO2006128479A1 (en) * 2005-05-30 2006-12-07 Telefonaktiebolaget Lm Ericsson (Publ) Technique for controlling handovers within a multi-radio wireless communication system
WO2007001215A1 (en) * 2005-06-28 2007-01-04 Telefonaktiebolaget Lm Ericsson (Publ) Means and methods for controlling network access in integrated communications networks
WO2007023786A1 (en) * 2005-08-23 2007-03-01 Nec Corporation System and method for synchronization between a plurality of base stations and mobile station in upstream link radio transmission
GB2455068B (en) * 2007-11-16 2010-07-28 Motorola Inc A base station for a cellular communication system and a method of operation therefor
CN101483898B (en) 2008-01-07 2012-08-08 华为技术有限公司 Method and apparatus for accelerating RRC connection establishment
US9398502B2 (en) 2008-07-17 2016-07-19 Zte Corporation Method for measuring adjacent areas
US8724594B2 (en) * 2008-07-17 2014-05-13 Zte Corporation Method for measuring adjacent areas
US9179373B2 (en) * 2009-07-23 2015-11-03 Qualcomm Incorporated Method and apparatus that facilitates redirecting wireless terminals between wireless networks
CN102118753B (en) * 2009-12-30 2014-02-05 上海无线通信研究中心 Spectrum reservation and carrier switching method based on micro base station-home base station system
US9049630B2 (en) * 2010-04-01 2015-06-02 Qualcomm Incorporated Facilitating baton handover in multi-carrier TD-SCDMA communications systems
CN102316463B (en) * 2010-07-06 2015-05-20 电信科学技术研究院 Carrier frequency regulation method and system
CN102421119A (en) * 2010-09-28 2012-04-18 中兴通讯股份有限公司 Method and system for reporting additional measuring result
GB2490311B (en) * 2011-04-18 2015-08-26 Intel Corp Communication between a user equipment and a base station
CN102957450B (en) 2011-08-26 2017-04-12 华为技术有限公司 Method and device for improving network quality, and wireless network controller
US9497769B1 (en) * 2012-04-12 2016-11-15 Sprint Spectrum L.P. Allocating carriers in a wireless communication system
US9078180B2 (en) 2013-02-26 2015-07-07 Qualcomm Incorporated Measurement reporting to avoid strong interference

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6208631B1 (en) * 1997-12-26 2001-03-27 Samsung Electronics Co., Ltd. Intra-cell inter-frequency hard handoff method in a CDMA cellular system
US6327472B1 (en) * 1998-11-11 2001-12-04 Telefonaktiebolaget Lm Ericsson (Publ) Arrangement, system and method relating radio communication
US20020019231A1 (en) * 2000-01-13 2002-02-14 Torgny Palenius Method and devices for improved handover procedures in mobile communication systems
US20020052206A1 (en) * 1998-12-07 2002-05-02 Fabio Longoni Cell load control method and system
US20040023665A1 (en) * 2002-04-16 2004-02-05 Kabushiki Kaisha Toshiba Methods and apparatus for alternative mode monitoring
US6701150B1 (en) * 2000-10-13 2004-03-02 Nortel Networks Limited Network driven cell switching and handoff with load balancing for wireless systems
US20040121777A1 (en) * 2001-04-26 2004-06-24 Uwe Schwarz Method and network element for controlling handover
US20050176440A1 (en) * 2004-02-06 2005-08-11 Nec Laboratories America, Inc. Load-aware handoff and site selection scheme

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3002645B2 (en) * 1996-12-06 2000-01-24 三菱電機株式会社 Busy channel switching system
CA2355646C (en) 1998-12-18 2009-10-06 Telefonaktiebolaget Lm Ericsson Methods and systems for controlling hard and soft handoffs in radio communication systems
US6522888B1 (en) 1999-08-31 2003-02-18 Lucent Technologies Inc. System for determining wireless coverage using location information for a wireless unit
CN1128560C (en) 2000-06-07 2003-11-19 深圳市中兴通讯股份有限公司 Cross-region switching method for mobile terminal
US6615044B2 (en) 2001-06-06 2003-09-02 Nokia Mobile Phones, Ltd. Method of WCDMA coverage based handover triggering

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6208631B1 (en) * 1997-12-26 2001-03-27 Samsung Electronics Co., Ltd. Intra-cell inter-frequency hard handoff method in a CDMA cellular system
US6327472B1 (en) * 1998-11-11 2001-12-04 Telefonaktiebolaget Lm Ericsson (Publ) Arrangement, system and method relating radio communication
US20020052206A1 (en) * 1998-12-07 2002-05-02 Fabio Longoni Cell load control method and system
US20020019231A1 (en) * 2000-01-13 2002-02-14 Torgny Palenius Method and devices for improved handover procedures in mobile communication systems
US6701150B1 (en) * 2000-10-13 2004-03-02 Nortel Networks Limited Network driven cell switching and handoff with load balancing for wireless systems
US20040121777A1 (en) * 2001-04-26 2004-06-24 Uwe Schwarz Method and network element for controlling handover
US20040023665A1 (en) * 2002-04-16 2004-02-05 Kabushiki Kaisha Toshiba Methods and apparatus for alternative mode monitoring
US20050176440A1 (en) * 2004-02-06 2005-08-11 Nec Laboratories America, Inc. Load-aware handoff and site selection scheme

Cited By (26)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8023469B2 (en) * 2005-04-29 2011-09-20 Telefonaktiebolaget L M Ericsson (Publ) Internetworking of cellular radio networks and wireless data networks
US20090131053A1 (en) * 2005-04-29 2009-05-21 Telefonaktiebolaget Lm Ericsson (Publ) Internetworking of Cellular Radio Networks and Wireless Data Networks
US20090149170A1 (en) * 2005-10-21 2009-06-11 Muhammad Ali Kazmi Apparatus and method for measurement reporting in a cellular telecommunications system
US20100254353A1 (en) * 2006-04-25 2010-10-07 Qualcomm Incorporated Polarization reuse and beam-forming techniques for aeronautical broadband systems
US8417181B2 (en) 2006-04-25 2013-04-09 Qualcomm Incorporated Polarization reuse and beam-forming techniques for aeronautical broadband systems
US20080014941A1 (en) * 2006-07-17 2008-01-17 Amer Catovic Methods and apparatus for soft-decision based inter-radio access technology handover triggering
US7643830B2 (en) * 2006-07-17 2010-01-05 Qualcomm Incorporated Methods and apparatus for soft-decision based inter-radio access technology handover triggering
US20080146231A1 (en) * 2006-10-27 2008-06-19 Nokia Corporation Method and apparatus for handover measurement
US8095134B2 (en) * 2006-10-27 2012-01-10 Nokia Corporation Method and apparatus for handover measurement
US8300596B2 (en) 2006-10-30 2012-10-30 Nokia Corporation Apparatus, method and computer program product providing extended measurement control signal for handoff measurement under interference coordination
US20080186919A1 (en) * 2006-10-30 2008-08-07 Nokia Corporation Apparatus, method and computer program product providing extended measurement control signal for handoff measurement under interference coordination
US8891487B2 (en) 2006-10-30 2014-11-18 Nokia Corporation Apparatus, method and computer program product providing extended measurement control signal for handoff measurement under interference coordination
US20080227074A1 (en) * 2007-03-13 2008-09-18 Byron Johnson Correlated electronic notebook and method of doing the same
EP2247155A4 (en) * 2008-01-23 2013-11-06 Fujitsu Ltd Moble communication system
US8908647B2 (en) 2008-01-23 2014-12-09 Fujitsu Limited Mobile communication system for reducing interference to an area
EP2247155A1 (en) * 2008-01-23 2010-11-03 Fujitsu Limited Moble communication system
US20100284373A1 (en) * 2008-01-23 2010-11-11 Fujitsu Limited Mobile Communication System
US9026124B2 (en) * 2009-03-31 2015-05-05 Futurewei Technologies, Inc. System and method for interference mitigation in a wireless communications system
US20100248737A1 (en) * 2009-03-31 2010-09-30 Futurewei Technologies, Inc. System and Method for Interference Mitigation in a Wireless Communications System
US20120230295A1 (en) * 2009-11-10 2012-09-13 Qualcomm Incorporated Method and Apparatus to Support HSDPA ACK/CQI Operation During Baton Handover in TD-SCDMA Systems
WO2011140399A1 (en) * 2010-05-06 2011-11-10 Qualcomm Incorporated Signal measurement in td-scdma multicarrier systems using downlink synchronization codes
US9084151B2 (en) 2010-05-06 2015-07-14 Qualcomm Incorporation Signal measurement in TD-SCDMA multicarrier systems using downlink synchronization codes
US20130189971A1 (en) * 2012-01-24 2013-07-25 Renesas Mobile Corporation Modified Measurement Procedures for User Equipments
US9094882B2 (en) * 2012-01-24 2015-07-28 Broadcom Corporation Modified measurement procedures for user equipments
US20160302109A1 (en) * 2015-04-10 2016-10-13 Telefonaktiebolaget Lm Ericsson (Publ) System, method, and apparatus for preventing offload return
WO2019068628A1 (en) * 2017-10-02 2019-04-11 Telefonaktiebolaget Lm Ericsson (Publ) Improved inter-frequency search order

Also Published As

Publication number Publication date
KR100894145B1 (en) 2009-04-22
US20120201227A1 (en) 2012-08-09
US8190157B2 (en) 2012-05-29
KR20070044013A (en) 2007-04-26
JP2008507173A (en) 2008-03-06
US8520640B2 (en) 2013-08-27
CN1985540A (en) 2007-06-20
JP4681609B2 (en) 2011-05-11
CN1985540B (en) 2011-03-23
US20090207811A1 (en) 2009-08-20
WO2006008591A1 (en) 2006-01-26

Similar Documents

Publication Publication Date Title
US10506480B2 (en) Method and apparatus for enhancing measurement in wireless communication system
TWI532401B (en) Method and apparatus for measurement reporting and event-triggered periodic measurement reporting in an evolved universal terrestrial radio access network
US6978138B2 (en) Inter-RAT cell reselection in a wireless communication network
EP1005760B1 (en) Hand-off based upon relative pilot signal strength
KR100557125B1 (en) Method and apparatus for generating handover neighbor list in cellular telecommunication system
DE69831058T2 (en) Apparatus and method for gently submitting in a wireless communication system
ES2375556T3 (en) Measurement and transfer between frequencies for communications without cables.
EP1540977B1 (en) Measurements in communications systems
KR101525717B1 (en) Channel quality measurements for downlink resource allocation
EP1691568B1 (en) A radio network controller, a mobile communication system, and a neighbor-cell-list filtering method
KR100753464B1 (en) Method for identifying pre-candidate cells for a mobile unit
KR100975715B1 (en) Method for determinning handoff in a mobile communication system
US7603123B2 (en) Method and system for performing a handoff in a wireless communication system, such as a hard handoff
JP4698916B2 (en) Method and apparatus for generating a pilot strength measurement message
DE60219159T2 (en) Method and system for handover triggering on WCDMA coverage basis
TWI322633B (en) Time division duplex method for determining whether to initiate handover criteria
EP1117269A1 (en) Method and devices for improved handover procedures in mobile communication systems
KR100897211B1 (en) Method and Apparatus for Minimizing Frequency Search Time in a Wireless Communication System
EP1553715B1 (en) A method for decide cdma frequency hard hand-off
KR100348676B1 (en) Methods and apparatus for inter-frequency handoff in a wireless communication system
JP4199187B2 (en) Soft handover area detection method and apparatus using inter-band measurement
CA2793193C (en) Performing inter-frequency measurements in a mobile network
US20010055968A1 (en) Mobile station and a method of reducing interference among radio channels in the mobile station
CN1112077C (en) Method and system for measuring signals in telecommunications system having MAHO
US7120437B2 (en) Method and apparatus for selecting carriers

Legal Events

Date Code Title Description
STCB Information on status: application discontinuation

Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION