EP1281289A1 - Procedures de transfert dans un systeme de radiocommunication - Google Patents

Procedures de transfert dans un systeme de radiocommunication

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Publication number
EP1281289A1
EP1281289A1 EP00917263A EP00917263A EP1281289A1 EP 1281289 A1 EP1281289 A1 EP 1281289A1 EP 00917263 A EP00917263 A EP 00917263A EP 00917263 A EP00917263 A EP 00917263A EP 1281289 A1 EP1281289 A1 EP 1281289A1
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EP
European Patent Office
Prior art keywords
handover
channel
channels
new
message
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.)
Withdrawn
Application number
EP00917263A
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German (de)
English (en)
Inventor
Rossella De Benedittis
Fabio Domenico Piana
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Siemens Holding SpA
Original Assignee
Siemens Mobile Communications SpA
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Filing date
Publication date
Application filed by Siemens Mobile Communications SpA filed Critical Siemens Mobile Communications SpA
Publication of EP1281289A1 publication Critical patent/EP1281289A1/fr
Withdrawn legal-status Critical Current

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Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W36/00—Hand-off or reselection arrangements
    • H04W36/0005—Control or signalling for completing the hand-off
    • H04W36/0055—Transmission or use of information for re-establishing the radio link
    • H04W36/0072—Transmission or use of information for re-establishing the radio link of resource information of target access point
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W56/00—Synchronisation arrangements

Definitions

  • the present invention relates to the mobile radio telephone sector, and more in particular, to a procedure for the execution of intercell handover in a third generation mobile telecommunication system.
  • Background art During the last ten years, the mobile radio telephone systems underwent a constant technological evolution that involved a gradual abandon of first generation systems, characterized by analogue modulations of the transmitted carriers, in favour of second generation systems, characterized on the contrary by digital modulations, as well as by an extensive digital processing (DSP) of the basic band signal converted into digital.
  • DSP extensive digital processing
  • the design of these systems availed of applications acquired in the military environment, following studies on the feasibility of transmissions suitable to preserve the confidentiality of the information transmitted and to assure a given immunity to the noises caused to sabotage purposes (jamming).
  • the targets have been reached thanks to an artificial widening of the modulation spectrum of the transmission carrier compared to the basic band spectrum.
  • the modulation technique is therefore called spread spectrum technique and consists in multiplying each low symbol-rate symbol of the signal to be transmitted with a code sequence, of the pseudo-noise type, at higher chip rate, whose scope is that to spread the information transmitted on a wide spectrum of frequencies, actually making it accessible only to whom is duly authorized to reception.
  • the spread spectrum receiver demodulates the signal received and reconstructs the original data performing a time correlation between the demodulated signal and a local copy of the code sequence used in the modulator. From the mathematical correlation between the symbols of the demodulated signal and the correct code sequence, the original signal at its maximum level is obtained at the output of the receiver, which therefore is discriminated from the noise and interference.
  • a spread spectrum use of modulation quite different from the previous military targets is foreseen. The peculiar use is to enable the simultaneous sharing of a same physical channel among more users, identified by different spreading codes.
  • CDMA Code Division Multiple Access
  • CDMA Code Division Multiple Access
  • CDMA Code Division Multiple Access
  • the relevant technique employs reciprocally orthogonal spreading code sequences, that is whose intercorrelation can be assumed as null. It just enables the discrimination among the different users summing up in the transmission band, since on a channel characterized by its own code sequence the signals of the other channels, as a result of the correlation, will appear as a noise.
  • the spread spectrum technique offers the additional advantage of a higher insensitivity to Rayleigh selective fadings, these last caused by multiple reflections along the path on-air of the signal transmitted, that obtains them from the fact that the spectral fraction concerned in high fading, is only a very small part of the spectrum globally occupied by the useful signal.
  • UMTS Universal Mobile Telecommunication System
  • PLMN Public Land Mobile Network
  • GSM Global System for Mobile communications
  • DCS Digital Cellular System
  • the GSM complies with specifications issued as recommendations by appropriate over-nation organizations (CEPT/CCITT, in ETSI/ITU-T environment) having the purpose to make the operation of the different telecommunication systems uniform in order to make them compatible among them and therefore capable of communicating.
  • the applicant acting in accordance with the 3GPP organization (3rd Generation Partnership Project) and the Chinese organization CWTS (Chinese Wireless Telecommunication Standards) is pursuing the development of its own third generation mobile telecommunication system based on the CDMA technique.
  • the aim for the near future is to preserve, where possible, the functional characteristics of the GSM, however intervening whenever the impact of the new CDMA technique necessarily requires ad hoc solutions. Consequently, before describing the embodiment of the invention, it is necessary to describe some operational peculiarities of the GSM system in order to enable to better understand the technical problem that the invention has to solve.
  • Fig. 1 shows a brief but clear block diagram of the functional architecture of a mobile system of the GSM, or DCS type; the same diagram can also be perfectly used to describe the CDMA system (TD_SCDMA) where the invention that shall be described resides.
  • portable telephone sets also vehicular ones are indicated with symbols MS (Mobile Station) hereinafter called also Mobile units, radio connected with relevant TRX transceivers (non-visible in the figure) belonging to relevant base transceiver stations BTS (Base Transceiver Station) spread on the territory.
  • BTS Base Transceiver Station
  • Each TRX is connected to a group of antennas whose configuration assures uniform radio coverage of the cell served by the BTS.
  • a group of N adjacent cells, that altogether engage all the carriers available to the mobile radio service, is called cluster; the same carriers can be re-used in contiguous clusters.
  • More base stations of the BTS type are connected through physical carrier to a common base station controller denoted BSC (Base Station Controller). More BTS altogether, governed by a BSC forms a functional subsystem defined BSS (Base Station System). More BSS (BSC) are connected to a mobile switching centre MSC (Mobile Switching Centre), directly or through a TRAU block (Transcode and Rate Adaptor Unit) that enables the submultipiexing of 16 or 8 kbit/s channels on the 64 kbit/s connection lines, optimizing the relevant use.
  • BSC Base Station Controller
  • MSC Mobile Switching Centre
  • TRAU block Transcode and Rate Adaptor Unit
  • the TRAU makes a transcoding from the 64 kbit s of the voice to 13 kbit/s of the GSM Full Rate (or to 6,5 kbit/s of the GSM Half Rate) enabling to address them with 16 kbit/s or 8 kbit/s flows.
  • the MSC block is in its turn connected to a switching centre of the terrestrial network PSTN (Public Switched Telephone Network) and/or ISDN (Integrated Services Digital Network).
  • PSTN Public Switched Telephone Network
  • ISDN Integrated Services Digital Network
  • HLR and VLR Two data bases are generally located at the MSC; the first one containing the steady data of each Mobile MS, the second one containing the variable data; the two bases co-operate to enable the system to trace a user that widely moves on the territory, extended to different European countries.
  • the BSC station controller is also connected to a Personal Computer LMT (Local Maintenance Terminal) enabling the man/machine dialogue, to an Operation and Maintenance Centre OMC performing the supervision, management alarm, evaluation of traffic measurements, etc., functions called O&M functions (Operation & Maintenance), and finally to a SGSN block [Serving GPRS (General Packet Radio Service) Support Node] specified in GSM 04.64 for the packet switching data service.
  • a Personal Computer LMT Local Maintenance Terminal
  • OMC Operation and Maintenance Centre
  • O&M functions Operation & Maintenance
  • SGSN block Serving GPRS (General Packet Radio Service) Support Node
  • the radio interface between MS and BTS is indicated with Urn, with A-bis that between BTS and BSC, with A-sub the interface between BSC and TRAU, with A the interface between TRAU and MSC or directly between this last and BSC, with T the interface RS232 between BSC and LMT, with O the interface between BSC and OMC, and finally with Gb the interface between BSC and SGSN.
  • the above mentioned interfaces are described in the following GSM recommendations: 04.01 (Urn), 08.51 (A-bis), 08.01 (A), 12.20 and 12.21 (O), 04.60 (Gb).
  • FIG. 2 shows an imminent and more advanced scenario compared to that of fig.1.
  • fig.2 at least one cell served by a BTS of the GSM system is indicated as adjacent to a cell served by a base station BTSC of the new system called 3G (3 rd Generation), which includes the invention object of the present application.
  • 3G 3 rd Generation
  • the descriptions of the relevant interfaces are indicated.
  • a station controller block BSCC connected both to the BTS and BTSC stations; the BSCC block represents a station controller opportunely modified versus a GSM only BSC to be able to support the new BTSC station (the dashed portion indicates the presence of the modifications).
  • the connection between BSCC and the new BTSC avails of an interface similar to the A- bis.
  • the interface on-air between BTSC and the Mobile units is called Uu to distinguish it from the Urn one of the GSM.
  • the Mobile units are called UE (User Equipment) to mean, under a different name, a different description of the interface on-air and of the Mobile units, that shall be consistent with the different design setting.
  • UE User Equipment
  • the aspect that mainly affect the design approach is the choice of the access kind one intends to implement on the physical channel to share the available band over the different users.
  • the more known access techniques are: the FDMA technique (Frequency Division Multiple Access) that performs the frequency division multiple access; the TDMA technique (Time Division Multiple Access) performing the time division multiple access; the CDMA technique (Code Division Multiple Access) performing the code division multiple access; and the SDMA technique (Space Division Multiple Access) that performs the space division multiple access.
  • each user can avail of its own frequency channel, not shared with any other user for all the time requested by the service, this case called SCPC (Single Channel Per Carrier) is typical of the analogue systems of first generation.
  • SCPC Single Channel Per Carrier
  • the whole radio spectrum is assigned to more users at different times, called time slots; during a time slot one user only can transmit and/or receive.
  • the CDMA technique the whole radio spectrum is assigned to more users at the same time, this technique has been previously explained.
  • the SDMA technique the whole radio spectrum is assigned to more users at the same time, similarly to what said for the CDMA technique, the discrimination among the different users occurs through acknowledgement of the different arrival directions of radio signals.
  • the GSM system employs a mixed technique FDMA-TDMA, which compared to the pure FDMA avoids an excessive use of carriers, while versus the pure TDMA it avoids the construction of frames too long and that cannot be proposed.
  • the new 3G system employs an FDMA-TDMA-SCDMA access that joins the advantages of the GSM to that of the CDMA technique. Both the GSM system and the new 3G system can take advantage from the use of an intelligent antenna, adding to the existing multiplexing also the SDMA one, this is certainly applied in the 3G system.
  • the user can send information towards the base station while it receives information from the same.
  • This communication mode is called Full-duplex and can be actuated using techniques both in the frequency field and in the time one.
  • the FDD technique Frequency Division Duplexing
  • the GSM employs different bands for the uplink path (uplink) and the downlink path (downlink). The two bands are separated by an unused gap band to enable the opportune radiofrequency filtering.
  • the TDD technique Time Division Duplexing
  • the new system 3G which the invention refers to, employs the TDD technique.
  • PLMN public mobile system
  • the problem has been solved employing ad hoc solutions for the FDMA-TDMA technique. These solutions cannot be directly transferred to the telephone systems according to the CDMA technique, at least concerning the radio interface that is the one having the major impact.
  • third generation mobile systems are at dawn, therefore several information on the definition of adequate signalling methods circulate only within restricted committees of companies participating in the definition of their own system, and cannot be considered of public domain yet.
  • the available band is subdivided as follows:
  • sub-band in the downlink direction (BTS ⁇ MS) 1805-1880 MHz; • gap band 20 MHz 1785-1805 MHz; channel band 200 kHz; N° of carriers per sub- band 374; time slot per carrier 8; N° of full-rate 2992 channels; N° of half-rate 5984 channels.
  • Fig. 3 shows the sequential organization of 8 time slots TS0, ..., TS7, or time slot, within a basic frame indefinitely repeated for the use of a generic carrier among those in use in a cell.
  • the aggregate of a carrier and of a time slot forms a physical channel of the Urn interface destined to support an information characterising the channel from the logic point of view.
  • the basic frame of fig.3 includes time slots all coming from a single transmission direction, being a FDD symmetric full-duplexing actuated in the GSM system.
  • the sequential frames are organized within more hierarchical levels observed by all the carriers used in the GSM system.
  • the burst can be of four different types according to the scopes (ref. GSM 05.02, paragraph . 5.2):
  • GSM 05.03 includes the following steps: block coding and convolutional coding that introduce redundancy increasing the bits from 260 to 456; reordering and partitioning and diagonal interleaving with 8 time slot depth to spread the burst errors over more bursts, addition of the stealing flag and obtaining of pairs of 2x58 bit sub-blocks; encryption, that is, sum bit by bit to a ciphering flow; and burst building with addition of the midamble and of bits TB to obtain the access burst.
  • the dispersion of the bits of a coded block over more bursts interlaced with the bits of the subsequent block and of the previous block reduces the bit loss per block, in case of corruption of a burst, improving the possibility that convolutional decoding reconstructs the origin information.
  • Frequency Correction burst This burst includes 142 useful bits at logic level "one" in order to allow the correction of the clock frequency of a Mobile unit when this burst is received.
  • Synchronization burst It includes a 64 bit "Synchronization Sequence” in midamble position and 2x39 Encrypted bits. This burst is received by the Mobile unit with an 8 time slot delay from the previous burst, therefore the Mobile that has already corrected the frequency of its own clock can discriminate the correct position of the " Synchronization Sequence " within the burst received, and then the starting instant of the time slot.
  • the Encrypted bits contain the information necessary to reconstruct the frame number FN (Frame number), completing the synchronization procedure.
  • Access burst It includes a 41 bit Synchronization Sequence in the starting position, followed by 36 Encrypted bits.
  • the guard period GP has 58, 25-bit duration; moreover there are 7 head bits TB and 3 tail bits TB.
  • This burst, of the short type, is typically used by the Mobile to send the first signalling to the network, for instance to perform an access in an originated call or in the handover, it has therefore lower duration than the previous bursts of the full type, and also the portion of time slot unused results higher.
  • This property actually enables the Mobile to send its message to the network with a non perfectly aligned timing, typically because altered by the propagation delay due to the variable distance between the radio station and the Mobile, without invalidating the seat of the adjacent time slots with the risk to disturb the communications underway.
  • a basic frame TDMA of 4.615 ms duration includes 8 time slots (TS0...TS7).
  • two different sequential multiframes are foreseen, out of which a traffic multiframe of 120 ms duration includes 26 basic frames TDMA, and a control multiframe of 253,38 ms duration, including 51 basic frames TDMA.
  • the two multiframes concur to form a unique superframe of 6,12 seconds duration, consisting of 1326 basic frames TDMA; and finally 2048 sequential superframes form an iperframe of 2.715.648 basic frames TDMA of 3h 28m 63s 760ms duration.
  • the Frame Number FN radio diffused within the cell is referred to the frame position in the iperframe.
  • Fig. 4 shows the organization of the logic channels supported by the frame structure TDMA of fig.3.
  • the set of logic channels foreseen includes a class of traffic channels TCH and a class of control channels.
  • TCH channels are of the full-rate TCH/F or half-rate TCH/H type depending on the fact that a single logic channel or two alternate links are assigned to the relevant time slot, or according to the channel coding used.
  • the control channels class includes the following main channels: a Broadcast Channel BCCH (Broadcast Control CHannel), a Common control channel CCCH (Common Control CHannel) and some dedicated Control channels DCCH (Dedicated Control CHannel).
  • BCCH Broadcast Control CHannel
  • CCCH Common Control CHannel
  • DCCH Dedicated Control CHannel
  • the BCCH channel includes three subchannels: a BCCH subchannel in a narrow sense, a synchronization subchannel SCH (Synchronization CHannel), and a Frequency correction Channel FCCH (Frequency Correction CHannel).
  • the CCCH channel includes three subchannels: a shared access subchannel RACH (Random Access CHannel), a grant subchannel AGCH (Access Grant CHannel), and a paging one PCH (Paging CHannel).
  • Dedicated control channels DCCH can be divided into two classes, that of "stand alone" channels SDCCH (Stand-alone Dedicated Control CHannel), and that of traffic associated channels ACCH (Associated Control CHannel). This last class includes two channel typologies, of low associated SACCH (Slow ACCH), and fast FACCH (Fast ACCH) type, respectively. After the general listing of channels it is worth to examine the same from the point of view of their formation and application.
  • the TCH/F traffic channels are bi-directional channels assigned to the Mobile units that have completed the access procedure to the network in call originated, or
  • traffic channels TCH/H carry voice coded at 6,5 kbit/s, or data, at circuit or packet switching, with net bit rate up to 4,8 kbit/s. Compared to the previous ones, they have a lower quality.
  • the control channel BCCH is a downlink unidirectional channel, point-multipoint, availing of time slot 0 of a carrier fO, said carrier BCCH. This channel is unique in the cell and is subject neither to Handover nor to frequency hopping.
  • the channel BCCH in a narrow sense, is used to diffuse general use system information, such as for instance: the configuration of channels within the cell, the list of BCCH carriers of the adjacent cells on which performing the level measurement, the identity of the Location Area and some parameters for the Cell Selection and Reselection activity, the complete Cell Identity, parameters for the operation of Mobile units in Idle Mode, and finally of the so-called RACH CONTROL parameters used to schedule the " access attempts of the Mobile units on the RACH channel.
  • FCCH and SCH channels carried by the Frequency Correction burst and by the Synchronization burst, respectively, are used by the Mobile units, in sequence, to synchronise the frequency of their own carrier, the starting of the locally generated frame (starting of the time slot 0), and the position of the same in the iperframe.
  • a TDMA system it is fundamental that the burst just falls in the assigned time slot, subject to interference generation in the adjacent time slot, this fact having to be checked also during the moves of the Mobile.
  • the BTS actuates to this purpose a procedure called ADAPTIVE FRAME ALIGNMENT (described in the recommendation GSM 04.03) through which it instructs the Mobile on the extent of the transmission advance in order that it receives a time slot on the uplink frame with a constantly fix delay of three time slots versus the transmission by the Mobile, notwithstanding the variability of the round-trip delay due to the variability of the MS distance from BTS.
  • the SCH channel includes a
  • BSIC field Base Station Identity Code
  • cell identification useful to the Mobile to identify the BCCH carrier of the serving cell from the BCCH carriers of the adjacent cells.
  • the control channel CCCH is a bi-directional channel serving the whole cell, it is subject neither to Handover nor to frequency hopping and employs the time slot 0 of the fO carrier.
  • the RACH shared access channel exists in the sole uplink direction to send the access requests of the Mobile units random distributed in time, towards the network; it is carried by the Access burst.
  • the multiple access can generate disputes on the possession of the channel that shall be solved, for instance, through a "slotted ALOHA" procedure, as indicated in GSM 04.08.
  • the two AGCH and PCH channels of the point-multipoint type exist in downlink direction only and carry the answers of the network to access requests made by the Mobile units on the RACH channel, and the so-called paging messages sent by the network towards the Mobile units in ended call procedures, respectively.
  • the dedicated control channels DCCH are bi-directional channels of the point-to- point type, subject to Handover and frequency hopping. They can carry signalling with bit rate ranging from 333,3 and 8000 bit/s.
  • SDCCH transport the signalling for the network functions, such as affiliation, etc. and for the control of calls up to the TCH channel assignment.
  • One SDCCH channel is assigned immediately after the access of a Mobile to the network.
  • the channels ACCH, SACCH and FACCH respectively, are included in the same multiframe of the associated traffic channels. More in particular: • A SACCH channel carried in uplink direction the transmission measurements made by a Mobile on the signal received by the serving BTS and by the adjacent cells; in downlink direction it carries different commands for the Mobile, such as timing advance, power control, etc, concerning the relevant TCH (first) SDCCH channel, as well as the information of the adjacent cells. • A FACCH channel is obtained through interleaving of the bits of its own channel TCH (bit stealing), and can therefore be used for a signalling with speed requirements higher than that of SACCH channels. Fig.
  • FIG. 5 shows two possible configurations of the logic channels inside the multiframe in case of medium/small BTS, that is equipped with a few transceivers, and in the case of medium/large BTS.
  • the figure includes a Legend that makes it self- explanatory to the purposes of description.
  • the 26-traffic-frame and associated signalling multiframes 1) and 1') are of course identical in the two cases, which differ in the 51 -control-frame multiframes.
  • the Mobile units perform power measurements on the BCCH carriers of the adjacent cells, and acquire also the relevant FCCH and SCH channels for a pre-synchronization (frequency, time slot, frame number, BSIC) in view of possible Handovers.
  • the remaining time slot 0 channels in downlink direction that is: BCCH in a narrow sense and CCCH (AGCH, PCH) are present in groups of four successive basic frames, with priority of CCCH groups.
  • BCCH in a narrow sense and CCCH ACH, PCH
  • CCCH ACH, PCH
  • the control logic channels of the interface on-air Um route the information in two propagation directions as messages exchanged between the Mobile and the network. This information passes over the frame of the Um interface and concerns, more or less, the remaining parts of the network visible in figures 1 and 2.
  • Fig. 6 shows the diagram of a protocol having several hierarchical levels used by the GSM system to manage the telephone signalling present at the different interfaces.
  • the protocol has been obtained from the one presently in use in mobile analogue systems TACS and in PSTN telephone systems, adjusting it to the new requirements of the interface on-air Um and to those deriving from the moving of users.
  • Some blocks (PHL, MAC, RRM . ) have been marked with a dashed line to indicate that the 3G system employs a suited version of the specified protocol.
  • the level structure enables to subdivide the signalling protocol functions in groups of superimposed blocks on the control plane (C-Plane), and to describe the same as a succession of independent stages. Each level avails of the communication services provided by the lower level and offers its own services to the higher level.
  • Level 1 of the above- mentioned protocol is strictly tied to the type of physical carrier used for the connection to the two sides of the different interfaces; it describes the functions necessary to transfer the bit flows on the radio connections to the interface Um and on terrestrial connections to A-bis and A interfaces.
  • Level 1 of terrestrial connections is described in recommendations CCITT G.703 and G.711.
  • Level 2 develops functions controlling the correct sequential flow of messages (transport functions) in the aim of implementing a virtual carrier without errors between the connected points.
  • Level 3 (called network level), and the higher levels, develop processing functions of the messages for the control of the main application processes.
  • APPENDIX APP1 includes a Legend with the terminology used in fig.6 and two tables describing the function of the blocks in fig.6, respectively referred to level 2 (Table A) and level 3 (Table B).
  • the Mobile equipment MS performs a given activity also in "Idle Mode", that is, when no dedicated channel has been allocated to the same.
  • the Mobile has the need, as first step to be able to communicate through the network, to continuously select a cell to associate with, during its moves.
  • the above mentioned activity falls under the "Cell Selection” function, described in recommendations GSM 03.22 and 05.08.
  • An additional requirement is that to monitor the paging messages to answer to a possible ended call.
  • the Mobile selects the cell to which associate with, making a scanning of the BCCH carriers it is able to receive from a given number of cells more close to its position within the cluster. This is made according to the method already mentioned, through the synchronization and reading of the content of BCCH broadcast channels.
  • the Mobile measures the power and quality of the signal received in order to update a list of six more favourite cells at least. The first cell in the list is the most reliable one and that to which the Mobile associates.
  • the MS access to the network occurs in the following cases:
  • the encryption method employs the ciphering algorithm A5 (Ciphering method) described in GSM 03.20. According to this method the level 1 data flow transmitted on DCCH or TCH is obtained summing up bit by bit the data flow of the user with a ciphering bit stream generated by algorithm A5 using a key, called "Ciphering Key", determined as specified in sub-clause 4.3. For a correct synchronization, the algorithm A5 needs to know the system frame number TDMA FRAME NUMBER.
  • the deciphering method applies the same phases of the ciphering method to the signal received, but in the reverse order.
  • Fig. 7 shows a Message Sequence Chart relevant to the case of an asynchronous inter-BSC Handover that had a successful result in a GSM system.
  • NETWORK protocol phases relating to the protocol entities generically called "NETWORK" have been neglected. This does not represent a damage to description purposes, since those skilled in the art who know the GSM specifications relevant to handover have sufficient elements to complete the missing part.
  • the synchronous handover can be read in the same figure where the reception phase by MS of the so-called PHYSICAL INFORMATION is deleted. Making reference to fig.
  • the procedure develops as follows: •
  • the network once completed a protocol phase that largely depends on the causes originated by the Handover and by the switching point, prepares a message addressed to the new BSC containing all the information necessary to the same in order that it provides a new channel for the handover.
  • the new BSC When the new BSC has operated as indicated above, it sends, through MSC, a HANDOVER COMMAND with the indication of the allocated channel and of all what required by the Mobile to place at first on the new channel, even if in a non perfect manner in terms of timing and power level. This command is sent to the Mobile by the old BSC to which the
  • HANDOVER COMMAND includes: the BSIC of the new cell, the
  • the message is 8 bit long, like the CHANNEL REQUEST message sent on the RACH channel by a mobile already associated to the cell, but having different content; for instance it includes the "Handover reference" field. Both the HANDOVER ACCESS message and the CHANNEL REQUEST message are then coded and sent on-air in short bursts, 88-bit long.
  • the HANDOVER ACCESS message is reiterated more times by the Mobile on the dedicated TCH channel until the reception of a full burst makes evident that it has been received.
  • the mobile receives the PHYSICAL INFORMATION transmitted by the new BTS in reply to the HANDOVER ACCESS message on the FACCH channel and ends the transmission of HANDOVER ACCESS.
  • the PHYSICAL INFORMATION contains the advance (TIMING ADVANCE) according to which the Mobile has to transmit the subsequent burst on the new channel. At this stage the Mobile can perfectly synchronize itself on the frame with the new BTS and adjust the transmission instant. The old ciphering key is maintained.
  • the Mobile sends a HANDOVER COMPLETE message on FACCH channel towards the new BTS, following which the new BSC communicates to the old BSC that it can release the old traffic channels and associated signalling.
  • Fig. 8 shows a brief procedure, in handshake form, to shows the failed Handover case, whether synchronous or asynchronous.
  • the Mobile cannot receive the PHYSICAL INFORMATION from the new BTS within a time foreseen, it switches on the old channel of. the old cell and sends a HANDOVER FAILURE message to start a Call Re-Establishment procedure.
  • Idle Mode and in Dedicated Mode The synchronization is in fact promoted by BTS through the emission of a copy of FCCH and SCH signals in the downlink multiframe at intervals of approximately 45.6 ms.
  • the holding of the synchronism of the Mobile in Dedicated Mode foresees the emission of the TIMING ADVANCE correction parameter by BTS on SACCH channels at intervals of approximately twice per second.
  • These synchronization mechanisms would go through a crisis in a 3G system of the TDD type [for instance: TD-SCDMA or TDD UTRAN (UMTS Terrestrial Radio Access Network)], characterized by well higher bit-rates and very stringent restrictions of the interference generated due to a too loose synchronization.
  • the uplink multiframe is identical to the downlink multiframe, so that a symmetry relation in the number of traffic channels and associated control in the two transmission directions, forcedly exists. This setting is not the best in coping with situations in which the traffic is highly unbalanced, such as for instance in connections with INTERNET in which the more engaged path is no doubt the downlink one. • The physical resource associated to a GSM channel is fix and cannot be modified, therefore it is not possible to dynamically vary the capability of the channel to face the changed traffic or message requirements.
  • the degree of reciprocal interference would be minimized equalling "burst by burst" the power received from the single isofrequential users and make the CDMA technique reliable.
  • the CDMA technique is preferred in the third generation systems just because it ca ⁇ avoid the drawbacks of the GSM highlighted before, particularly those due to the low bit-rate, to the need to have an accurate planning of the frequency, to the inability to efficiently manage asymmetric traffic.
  • different companies of the sector are fostering for the third generation systems, the near future target is that of a reciprocal agreement to produce a number of universal specifications UMTS greatly detailed, as it was done in the past for the GSM in the sole European environment.
  • PN Pseudo-Noise
  • the Walsh 0 function is employed for the pilot channel.
  • the remaining 63 Walsh coding are used for the synchronization channels (Synch channels), of call (Paging channels) and of conversation (Traffic channels).
  • the data speed at the encoder input can range from 1200 to 9600 bit/s.
  • All the channels of a base station CDMA form the so- called "forward link", which in practice is the signal transmitted towards the Mobile units.
  • the signal transmitted by the mobile differs from that of the base station for the different channel coding and the type of modulation used (Offset-QPSK).
  • the pilot sequences PN which in the receiver of the mobile are synchronised at the pilot signal of the base station, are used again to spread-spectrum modulate the modulation data. Another characteristic differentiating the signal of the mobile is that this last does not transmit any pilot signal.
  • a closed loop control of the transmission level is foreseen, between the base station and all the active Mobile units, to compensate the variability of attenuation due to the different distance from the antenna and channel fading.
  • the transmission power of all the Mobile units can be adjusted, in such a way that the intensity of signals at input of the receiver of the base station has approximately the same level.
  • Joint detection in decoding the information of the user x, the information of y and z co-located users is also decoded, to the purpose of subtracting the signal of the latter from the signal received, so that the signal of user x does not suffer the interferent effects.
  • a third point is that of how to employ the new synchronization means in the protocol phases foreseeing an access of the Mobile to the radio frame of the serving cell, or adjacent cell in case of handover.
  • a fourth point is how to share within the multiframe the logic channels including system information, particularly if concerning synchronization, compatibly with the allowed signalling delays.
  • a fifth point is how to obtain that the signals received from more mobile stations arrive with the correct power level.
  • a CDMA system UMTS candidate, shall maintain the maximum general character in the function of the pilot signal to help the standardization process;
  • the pilot signal is associated to the cell and is used as identifier of the same towards the mobiles (see specification IS-95), this acknowledgement should be more expensive and also less reliable due to additional fields.
  • the pilot signal is modulated, as we shall see later on, to carry information on the common service channel; the modulation is necessarily referred to a fix pattern, which the additional fields would no more maintain as such.
  • a message of the SCH type is transmitted in a unique full burst, therefore its acquisition occurs in the time of a radio frame.
  • the SCH channel is preceded by the FCCH channel that can be recognized by the mobile stations consequently the MS know when to wait for the SCH channel and therefore the SFN parameter.
  • a BCCH message is transmitted in more frames (typically 4), hence the acquisition takes a longer time. Even if in a CDMA system the pilot signal allows to know when the common signalling channel starts, it is not so sure that it carries the information of interest (for instance it could contain a Paging).
  • the mobile station has to decode the BCCH channel of the destination cell to recover the SFN parameter.
  • the sole procedure that in lack of the means offered by the present invention would go through a crisis due to the new location of the frame number SFN in the intercell handover, just because it does not tolerate the execution delay due to the acquisition time of the SFN value of the new cell.
  • the knowledge of the system frame number SFN comes into play in all the procedures that foresee an access of the Mobile unit to the network, such as for instance in a call originated by the Mobile unit, in a call ended towards the Mobile and in the handover. It is used to complete the synchronization, to be able of coding and decoding the information in a synchronous mode between the two interacting stations and to start the ciphering/deciphering on the dedicated channel.
  • the acquisition of the SFN value by a Mobile unit demands an initial delay due to the reading of the BCCH channel of the serving cell. Afterwards said knowledge is maintained for all the time the mobile unit remains synchronized to the network and is refreshed at any new reading of the BCCH channel. This means that, suffered the initial consequences, there are no more delay problems due to SFN inside the serving cell in the execution of procedures related to the same.
  • the intercell handover does not fall under this scheme, because the Mobile unit abandons the serving cell and appears at an adjacent cell, of which it does not know the SFN value (this also in case of synchronous handover if the serving cell is the destination one are not synchronous even for frame number). The handover is for its own nature a delicate operation made during the conversation.
  • scope of the present invention is to indicate a procedure for the processing of the intercell handover in a UMTS system (availing of the CDMA technique), maintaining the handover high processing speed without subtracting resources to the Payload, notwithstanding the subjects raised in the previous discussion would not allow it.
  • Main scope of the present invention is a procedure for the processing of the synchronous intercell handover in a third generation mobile telecommunication network, as described in claim 1.
  • Further object of the invention is a procedure for the processing of the intercell asynchronous handover in a third generation mobile telecommunication network, as described in claim 2.
  • - fig. 1 shows a block diagram of a mobile system of the GSM or DCS type
  • - fig. 2 shows a block diagram of a scenario including a GSM system and a 3G mobile system according to the present invention
  • - fig. 3 shows a hierarchy of sequential frames of the signal transmitted to the interface radio Um of the mobile system GSM of figures 1 and 2;
  • - fig. 4 shows a logic channel structure supported by the hierarchy of sequential frames of fig.3
  • - fig. 5 shows two possible organizations of the logic channels of fig.4 within the hierarchy of sequential frames of f ⁇ g.3;
  • - fig. 6 shows a block diagram of a protocol having more hierarchical levels governing the operation of the two mobile radio systems of fig.2;
  • - fig. 7 shows a message sequence chart relevant to a an intercell handover protocol limited to the exchange of messages al the interface radio Um of the mobile system
  • GSM of fig.1 GSM of fig.1 ;
  • - fig. 8 shows a message sequence chart relevant to a handshake phase concerning the handover failure case of fig. 7;
  • - fig. 9 shows a hierarchy of sequential frames of the signal transmitted to the radio interface Uu of the mobile system that includes the present invention
  • - fig. 10d shows the structure of the DwPTS burst, included in the basic frame of fig.10a;
  • - fig. 10e shows the structure of the UpPTS burst included in the basic frame of fig.10a;
  • - fig. 10f shows a general structure of bursts TsO Ts6 contained in the basic frame of fig.10a;
  • - fig. 10g shows an actual structure of bursts TsO, .... Ts6 contained in the basic frame of fig.lOa;
  • - fig. 11 shows a diagram of a criterion employed in the mobile system 3G to share among the different cells the different DwPTS bursts available of fig.10d, together with groups of SCRAMBLING CODEs and groups of midambles that can be referred to the bursts of figures 10f, g;
  • - fig. 12 shows a table completing the criterion of fig.11 with the sharing of the available UpPTS bursts of fig.lOe;
  • - fig. 13 shows a logic channels structure supported by the sequential frame hierarchy of fig. 9;
  • - fig. 15 shows a representation of physical and logic channels relevant to a basic frame of fig.10a; - fig. 16 shows a Message Sequence Chart relevant to a protocol of Intra-system Intercell Handover at the radio interface Uu of the 3G mobile system in which the present invention is applied;
  • Appendix APP1 shows a TABLE A that includes a very general functional description of level 2 protocols used in GSM and 3G mobile systems of fig.2, and a similar TABLE B relevant to level 3 protocols;
  • Appendix APP2 shows some TABLES 1 through 9 specifying some physical and functional characteristics of the radio interface Uu of the 3G mobile system where the present invention is applied.
  • Fig. 9 shows the sequential organization of 7 time intervals, or time slots, in addition to other three special time slots, which shall be described afterwards, within a 3G basic frame indefinitely repeated for the use of a generic carrier among those in use in a cell (much less in number than those used in the GSM because broad band employed).
  • the basic frame of fig. 9 includes m time slot UL#0, ..., UL#m (UpLink) coming from the Mobile units MS and n time slot DL#n, ..., DL#0 (DownLink) coming from BTSC (fig.2), being a full-duplexing of TDD type implemented in the 3G system.
  • the set consisting of a carrier, a time slot of utilization of the same and a spreading code forms a physical channel of the Uu interface destined to support an information characterizing the channel from the logic point of view.
  • the sequential frames are organized in more hierarchical levels observed by all the carriers used in the 3G system.
  • the carriers transmitted by a BTS transport reciprocally synchronised frames, thus simplifying the synchronization between adjacent cells. Without setting limits to the present invention, it is convenient to make a general frame synchronization among all the cells of the different clusters, featuring the 3G system as a TD-SCDMA system (Time Division Synchronous Code Division Multiple Access).
  • the total duration of the basic frame is 5 ms.
  • 24 basic frames 3G form a 120 ms traffic multiframe.
  • 48 basic frames 3G form a 240 ms control multiframe 3G.
  • 24 x 48 1152 basic frames 3G form a superframe 3G of the duration of 5,76 s.
  • the 1152 frames can come from either 48 traffic frames or 24 control frames.
  • 2048 superframes 3G form an iperframe 3G consisting of 2.359.296 frames 3G of the total duration of 3h 16m and 36s.
  • the comparison between figures 3 and 9 shows that the GSM and 3G systems adopt values rather close to the different orders of time division.
  • the hierarchy showed is not binding, for instance it is possible for signalling opportunity to consider two consecutive basic frames of fig. 2 as two subframes of a new frame having double duration, belonging to a multiframe of 72 new frames having 720 ms total duration.
  • the guard period GP is used to avoid interference between uplink and downlink transmissions, as well as to absorb the propagation delays between the mobile station and the base station when the first one sends the first signal on the UpPTS channel; and represents the DL/UL switching point.
  • FIG. 10a, 10b and 10c show different organizations of the basic frame 3G, the first two figures are relevant to a configuration having higher symmetry versus the remaining one.
  • Fig.lOa shows the basic frame of fig.
  • Fig. 10b shows a completely symmetric situation of three useful time slots in the two directions and the Downlink Td6 time slot available for the signalling, while fig.10c shows a asymmetric situation with two uplink time slots and four downlink ones more suitable for Internet connections.
  • Fig. 10d shows that the downlink pilot time slot DwPTS includes a 32-chip guard period GP followed by a 64-chip SYNC sequence.
  • Fig. 10e shows that the uplink pilot time slot UpPTS includes a 128-chip SYNC1 sequence followed by a 32-chip guard period GP.
  • fig. 10f shows that the common structure of useful time slots TsO, ..., Ts6 includes two fields having equal length of 352 chips for data, placed respectively before and after a
  • Each one of the two fields given in fig.10f is modulated by a pre-set number of sequence codes to generate an equal number of radio channels in the band of the spread spectrum, which individually occupy the whole band and represent a same number of so-called resource units RU (Resource Unit) put at disposal of the service and of the signalling;
  • the midamble on its side includes a training sequence used by the BTSC station and by the Mobile units to evaluate the impulse responses of the number of radio channels generated, for the purposes mentioned later on.
  • T s k Q k x T c , where Q k is a spreading factor SF (Spreading Factor), freely selected among 1 , 2, 4, 8, and 16, corresponding to said number N of code sequences; T s is the duration of a transmitted symbol, and _T_ is the fix duration of the chip.
  • SF Spread Factor
  • Table 1 shows the number of symbols that can be obtained from each Data field of the main burst of fig.10f for the different spreading factor SF of the sequences of CDMA modulation.
  • Table 2 shows the approximate data transmission speed for the different RU S Fi...i6- From the information supplied we notice that employing a generalised spreading factor equal to 16 in the frame of fig.lOa, each one of the 7 useful time slots will carry 54 symbols, to which 10 symbols of UpPTS, 6 DwPTS symbols, 6 equivalent symbols for the GP period shall be summed up, totalling 400 symbols.
  • the frequency bands available for the 3G system can be allocated around 2 GHz and have variable widths according to the spectrum availability. More in particular, the area of availability is currently included between 1785 and 2220 MHz in noncontiguous bands with width ranging from 15 to 60 MHz, therefore it is possible make the 3G service coexist with that offered by other systems.
  • Table 3 of Appendix APP2 shows the main modulation parameters of the burst in fig.10f.
  • the spreading sequences that modulate data (symbols) are sequences known as Walsh(n) functions.
  • the scrambling confers a pseudo-noise characteristic to the sequence it is applied to.
  • Spreading ⁇ scrambling operations can be compared to the application of a spreading code characteristic of the cell.
  • the knowledge of the particular combination of spreading and scrambling codes assigned to the RU enables to transmit the signals to the radio interface Uu and to reconstruct the original signals submitting the signals received to descrambling and despreading inverse operations.
  • a similar approach applies to the midambles.
  • the next fig, 11 shows the sharing criterion of the following entities among the different cells of the 3G system: SYNC sequences of the burst DwPTS, scrambling codes, midambles, and SYNC1 sequences of the UpPTS burst (called also signatures).
  • SYNC sequences of the burst DwPTS SYNC sequences of the burst DwPTS
  • scrambling codes SYNC1 sequences of the UpPTS burst
  • SYNC1 sequences of the UpPTS burst called also signatures.
  • a Scrambling code group consisting of 4 scrambling codes, for a total of 32 groups and 128 codes, assigned in the sequential numeric order as indicated in the figure, is associated to each DwPTSn.
  • a respective group of 4 midambles is associated to each one of the 32 Scrambling Code Group, for a total of 32 groups and 128 midambles, assigned meeting the same numeric order of the scrambling codes.
  • the SF (Max 16) versions of which, obtained from SF time shift shall be supplied, as said above, when the need arises.
  • Fig. 12 indicates the sharing criterion among the different cells of the 3G system of the signature sequences SYNC1 , each one corresponding to the content of the Uplink Pilot time slot UpPTS.
  • each line represents a carrier (cell) identified by its own DwPTS pilot for a total of 32.
  • a group of 8 different sequences SYNC1 is associated to each downlink pilot DwPTS, for a total of 256, assigned according to the numeric sequence of the figure.
  • a Mobile unit random selects one of the eight sequences SYNC1 associated to a pilot signal DwPTS to have access to the network through the cell identified by that specific pilot signal.
  • a Legend in the figure gives the lengths of the different elements of the two tables.
  • the different time slots of the basic frame of fig.lOa are, in a lesser or higher quantity, subject to beamforming by a resident intelligent antenna, of course in the sole BTSC.
  • the time slots subject to beamforming are associated to a set of complex beamforming constants used in the spatial, or space-time filtering, made by BTSC on the transmission and reception time slots.
  • the Mobile performing the roaming, or that is in idle state, is always subjected to the affiliation procedure that associates it to a "Location area" and in particular to a cell, of which it ' has to know the semipermanent data (frequency, DwPTS, basic Midamble, Scrambling code, UpPTS group).
  • Appropriate system messages fulfil the purpose, which shall be then integrated with subsequent "ASSIGNMENT" messages, to assign the remaining elements (Midamble shift code, spreading factor and spreading code, beamforming constants, transmission power and time advance) that more properly configure the channel assigned in temporary mode to a connection that involves the radio interface Uu.
  • a pilot DwPTS is transmitted by a generic BTSC station without beamforming, or with sector beamforming, and enables the Mobile to perform a Cell Selection procedure when it switches from off to on.
  • the Mobile in its non volatile memory SIM (Subscriber Identity Module) has stored all the frequencies in use in the 3G system and the corresponding pilot DwPTS, in order that it can start a synchronization downlink scanning to determine the DwPTS pilot received with the highest power, so as to affiliate itself to the relevant cell and proceed to the reading of the broadcasting diffused system information.
  • SIM Subscriber Identity Module
  • the discrimination of the DwPTS pilot requires the use of a digital filter whose coefficients are programmed to be coupled to the SYNC sequence examined time by time. During the synchronization a tracing algorithm of the frequency that enables to remove the frequency offset from the signal received can be active.
  • Other functions tasked to the downlink pilot DwPTS which are only briefly outlined for brevity sake, are the On-air synchronization of adjacent base stations, and the indication to the Mobile units of the starting position and of the interleaving period of a common control primary channel (CCPCH) from which to obtain broadcast diffused system information. This last function can be obtained with different techniques known to those skilled in the sector.
  • CPCH common control primary channel
  • the uplink pilots UpPTS are initially started by the Mobile units in the Affiliation procedure (Location updating) that follows the Cell Selection phase and then, during first and additional random accesses, to the network in the Cell re-selection procedure and in the asynchronous handover.
  • a mobile randomly selects one of the eight sequences SYNC1 to be sent uplink and starts sending it.
  • the eight sequences of a group are all orthogonal among them, so that they can be simultaneously transmitted by a same number of Mobile units and be discriminated by the base station BTSC without interfering. What said above, applies to all the 256 SYNC1 sequences.
  • the BTSC station that acknowledges a SYNC1 sequence, measures the relevant delay and the power level received and transmits an access timing adjustment message (Timing Adjustment) to the Mobile on single burst to limit the delay in a sole frame, using an appropriate physical channel P-FACH (described below).
  • Timing Adjustment an access timing adjustment message
  • the adjusted values shall be used by the Mobile to send the next message.
  • the starting power control and synchronization reduce the total interference on the channels assigned by the network in response to the SYNC1 sequences.
  • the Mobile on receipt from the network of a co-ordinated response to the transmission of the SYNC1 sequence, stops the transmission of the pilot UpPTS. At the assignment of a dedicated channel, the holding of the synchronization and of the correct transmission power is entrusted to the use of the midamble.
  • a unique basic midamble can generate up to 16 different midambles in a cell, specified by as many coded shift-time values, as are the different versions of the burst that can contemporarily coexist in the time slot, thanks to the maximum spreading value SF.
  • Midambles are subject to the same beamforming and to the same transmission power of the data present in the bursts housing them.
  • the code specifying a midamble is that of a training sequence for the evaluation of the impulse response of the associated radio channel.
  • the functions connected to the midambles are:
  • Measurements of the Signal/Interference power ratio are made both uplink and downlink to graduate the transmitted power.
  • a mechanism is used based on an internal control loop, it is very fast since it is operated by the first sample of the impulse response, completed by a slower external loop based on quality measurements.
  • Level 1 fields are foreseen in the main burst for ' the allocation of commands to the transmitters allowing the fast internal loop.
  • - Holding of the uplink synchronisation The BTSC station calculates the discrimination instant of the midamble compared to its own time basis, it compares this instant with the previous corrected value, the difference being the new TIMING ADVANCE value to be sent to the mobile for the correction of the initial transmission instant of the next burst.
  • the accuracy in the uplink transmission is
  • level 1 fields are foreseen in the main burst for the allocation of commands to the transmitters enabling a quick control.
  • Fig. 10g shows a possible configuration of the main burst of fig.10f in which two
  • L1 Level 1 fields can be seen, placed immediately at the two sides of the midamble. Each one of the two L1 fields is also adjacent to an additional field, jointly destined to a SACCH channel that shall be described afterwards.
  • Table 4 of Appendix APP2 shows the meaning, the position in the burst, and the dimensions of L1 fields in fig.10g.
  • the indication of the third column means a spreading factor 16.
  • the table includes three 2- bit fields called PC, SS, and SFL.
  • the fields PC and SS include commands addressed to the transmitter to perform the Power Control (PC) and Synchronization Shift (SS) functions.
  • the fields SFL is a Stealing Flag used in the same way as in the GSM:
  • the first bit of the SFL symbol controls the pair bits of the burst of fig.10g, while the second bit controls odd bits. If the value of a control bit is set at "1", the corresponding pair or odd bits of the burst shall transport signalling of higher Level (FACCH), otherwise the corresponding pair or odd bits of the burst shall transport data, as for instance for the voice.
  • the SFL value is fix for the whole interleaving period along N frames, that depends on the service.
  • the total of 6 bits of fields PC, SS, and SFL are equivalent to 96 chips (6 symbols).
  • DPCH Dedicated Physical CHannel
  • P-CCPCH Primary-Common Control Physical CHannel
  • S-CCPCH Secondary-Common Control Physical CHannel
  • P-RACH Physical Random Access CHannel
  • P-FACH Physical Forward Access CHannel
  • PDPCH Packet Data Physical CHannel
  • TCH Traffic CHannel
  • SACCH Small Associated Control CHannel
  • FACCH Fast Associated Control CHannel
  • BCCH Broadcast Control CHannel
  • PCH Paging Channel
  • AGCH Access Grant CHannel
  • optCH Optional CHannel
  • COCH Common Omnidirectional Channel
  • RACH Random Access Channel
  • FACH Forward Access Channel 1 burst
  • PDTCH Packet Data Traffic Channel
  • PACCH Packet Associated Control Channel
  • the two peculiar physical channels of the 3G system are undoubtedly the two pilot time slots DwPTS and UpPTS.
  • the downlink pilot DwPTS performs, in the new context, functions similar to those of the bursts supporting the SCH and FCCH channels of the GSM, with the exception due to the fact not to carry the frame number TDMA, which should therefore be routed by the broadcast diffused System Information.
  • the uplink pilot UpPTS is unmatched in the GSM, since it is more appropriate to a TDD frame.
  • the Mobile units are compelled to use a signature SYNC1 carried by UpPTS to have a time and power synchronization of the signal that shall be transmitted in the next message, typically on a random channel RACH to request that a dedicated channel is assigned.
  • the time and power synchronization requirement takes place for the first accesses to the network, afterwards, when the network has assigned a dedicated channel to the mobile (UE), provides the midamble; therefore up to that moment the SYNC1 sequence is necessary.
  • the access and synchronization mechanism is therefore different from the GSM, just for the different physical setting out of the 3G system.
  • the primary channel P-CCPCH for instance, is always allocated in the downlink time slot, immediately before the DwPTS pilot (see fig. 10a). Its spreading factor is always16.
  • the channel has a fix radiation pattern that can be omnidirectional or subject to a limited beamforming to give a given shape to the cell. The lowest shift value of the midambole is always associated to the channel.
  • the primary channel P-CCPCH transports 23 information bytes of higher Level and supplies information on the other common control channels.
  • the secondary channel S-CCPCH can be freely allocated in all the downlink time slots.
  • the spreading factor is always 16 and can be subjected to an omnidirectional or adaptive variable beamforming.
  • the P-RACH random channel can be allocated in one or more uplink time slots, whose number depends on the traffic foreseen, and is used to transport the messages of the Mobile units with the request of assignment of a service channel.
  • the spreading factor is always 16 and can be subjected to an omnidirectional or adaptive variable beamforming. It partly contains Level 1 information.
  • the P-FACH direct channel can be freely configured in all the downlink time slots.
  • the spreading factor is always 16 and can be subjected to an omnidirectional or adaptive variable beamforming. it partly contains Level 1 information.
  • the channel P-FACH carries the replies of the network to each sequence SYNC1 correctly revealed.
  • the reply message is supplied on a single burst to limit the delay to one single 5 ms basic frame.
  • the network through the reply attached to the P-FACH channel, gives the mobile station that has sent the sequence SYNC1 an identifier of the acknowledged sequence and of the indications on the correct advance and power level to be used in the transmission of the next message, that shall be very likely a request for a service message on the P-RACH channel.
  • the access to the network through the SYNC1 sequences involves in parallel the fact to have determined a method to assign the Mobile units the channels P-RACH, P-FACH, and P/S-CCPCH (in the present case AGCH) that come into in the immediately next phases.
  • P-RACH Physical Random Access Control
  • P-FACH Physical Random Access Control
  • P/S-CCPCH in the present case AGCH
  • mapping must associate each one of the 8 SYNC1 sequences to a channel P-FACH.
  • Each P-FACH must be the destination of one SYNC1 at least.
  • the mapping from P-FACH to P-RACH must create an association with a P-RACH that has been configured.
  • Each configured P-RACH must be the destination of at least one P-FACH.
  • the mapping from P-FACH to AGCH must create an association with a P/S-CCPCH that has been configured.
  • the channel P/S-CCPCH shall carry an AGCH.
  • Each configured AGCH shall represent the destination of the mapping of at least a P-RACH.
  • the information defining the different links foreseen is included among the broadcast diffused system information, and therefore a link is known by the Mobile and by the network even before establishing a connection.
  • Table 8 of Appendix APP2 gives an example of such association of groups of sequences SYNC1 and channels P-FACH. As it can be noticed from the table, increasing the number of time slots used by the channels P-FACH, the SYNC1 groups consequently increase and the number of elements in the single groups averagedly decreases. The fact to have established a link like the prospected one enables the Mobile to have a reply from the network, enabling to profitably make the appropriate corrections.
  • Physical dedicated channels DPCH have a burst structure described in fig. 10g.
  • the channel PDPCH has the same structure of DPCH dedicated channels, the meaning of Level 1 fields obviously changes.
  • logic channels mapped in physical channels of TABLE 7 they are also called transport channels because they deliver to the Physical level of the radio interface a block supplied by the upper Level of the protocol. From the functional point of view, logic channels of Table 7 are grouped as indicated in Fig. 13.
  • CONTROL CHANNELS includes the following channel types: BROADCAST
  • TCH/F is a TCH Full-rate
  • TCH/H is a TCH Half-rate, and the optional channels are indicated with NCH
  • TCH Traffic CHannels
  • the whole payload is mapped in the physical channel DPCH in the portion not used for Level 1 signalling and SACCH channels. It is possible to map an RU SF 8 or one, or two, RU S FI 6 - For high data rates, TCH channels can be combined. They are subject to beamforming.
  • FACCH Flust Associated Control CHannel
  • SACCH Slow Associated Control CHannel
  • TCH Traffic Channel
  • Fig. 14 compares the GSM 26-frames traffic multiframe in 120 ms with the 24-frame 3G multiframe in 120 ms. In the upper line, six 260-bit blocks at the output of the voice encoder common to the two systems are mapped.
  • TCH traffic channels
  • the 26 th frame is used to perform measurements on close BTS stations without voice or data loss. In the 3G system this kind of frames is not present, therefore the channels SACCH must be mapped within each TCH channel.
  • BCCH Broadcast Control CHannel
  • the channel BCCH is mapped in two RU SF16 of the physical channel P-CCPCH.
  • the channel BCCH shares the spaced frames of the physical channel together with the PCH channel or other common control channels.
  • the sequence modulation of the pilot DwPTS indicates the starting of an interleaving period of the channel P-CCPCH containing the BCH channel (Broadcast Channel).
  • the layout of the physical channel P-CCPCH is signalled in the system information.
  • Table 9 in Appendix APP2 gives an example of multiplexing of common control channels BCCH and PCH in the multiframe of 48 control frames.
  • the multiframe is subdivided into spaced blocks, four basic frames long.
  • PCH Paging CHannel
  • AGCH Access Grant CHannel
  • iCBCH Cell Broadcast Channel
  • NCH Notification Channel
  • RACH Random Access CHannel
  • FACH Forward Access CHannel
  • PC Power Control
  • SS Synchronization Shift
  • PDTCH Packet Data Traffic CHannel
  • PACCH Packet Associated Control CHannel
  • each downlink time slot is coupled to an uplink time slot, therefore it is supplied a natural connection among all the logic channels sharing the combination of channels of a time slot multiframe.
  • This fact is employed in the GSM to associate a PCH channel to a RACH channel and to associate a RACH with an AGCH. If the combination of channels is present on more than one time slot within a cell there is a method to distribute the Mobile units among the channels to the purpose of sharing the load.
  • there is not a natural connection of the highlighted type consequently a similar connection among the control channels shall be built through its definition.
  • the broadcast diffused system information shall contain a trace of the agreed definition.
  • the control channels considered, represent an allocation set called CCHset (Control CHannel Set).
  • CCHset Control CHannel Set
  • Fig. 15 shows a possible layout of a CCHset and of a P-FACH channel within a 3G 5 ms basic frame.
  • Fig. 16 is a Message Sequence Charts showing an Intra-system Intercell handover procedure, whether synchronous or asynchronous, made on dedicated channels according to the teachings of the present invention and to all the notions supplied on the 3G system up to now.
  • the reasons for the handover are those already described when treating the GSM.
  • the handover procedure is always started on the network's initiative and includes: - The interruption of normal operations except for the radio resource management RR (level 3)
  • the Mobile unit after receipt of the HANDOVER COMMAND message, starts releasing the old connections to the different Levels of the protocol, it disconnects the physical channel, directs the switching towards the channels assigned in the new cell, synchronizes at the downlik pilot DwPTS of the new cell, and starts establishing the new connections at lower Levels (this includes the channel enabling, their connection and the establishment of data connections).
  • the HANDOVER COMMAND message includes:
  • the characteristics of the new channels including the correct indication of the AGCH channels and of FACCH and SACCH channels that shall be used for the multiresource configuration and, optionally, the power level to transmit on the new channels.
  • the message can also contain the definitions of the channel modes that must be applied for one or more sets of channels. If a set of channels previously not defined is defined by the HANDOVER COMMAND message, the message itself shall include a definition of the channel mode for the new set of channels.
  • the characteristics of the new cell that are necessary to successfully communicate including the ' data that enable the Mobile to use the pre-knowledge on synchronization it acquires from the measurement procedure (for instance, the cell scrambling code + the frequency and power level of the channel PCCPCH/DwPTS).
  • the power level of the PCCPCH/DwPTS channel shall be used by the Mobile for the initial power on, on the new channel(s).
  • the power level defined in this Power command shall be used by the Mobile unit for the initial power on, on the new channel(s) and shall not affect the power used on the old channel(s).
  • Some parameters for the access to a dedicated channel due to handover among which: the identifier of the group of SYNC1 sequences allowed in the new cell, the description of P-FACH channels.
  • Timing advance value to be used in the new cell (optional: used for synchronized cells).
  • the HANDOVER COMMAND message shall not include an IE (Information Element) of setting of the ciphering mode indicating "start ciphering", unless a CIPHERING MODE
  • COMMAND message has been previously transmitted; in the example shown, if a similar HANDOVER COMMAND message is received, it shall be considered wrong and a HANDOVER FAILURE message shall be immediately returned due to "Unspecified protocol Error", and no further action shall be undertaken.
  • An optional target mode information element VGCS Voice Group Call Service
  • VGCS Voice Group Call Service
  • the target mode VGCS information element shall also indicate the number of the group ciphering key for the group ciphering key that must be used on the new channel, or, if the new channel is not ciphered.
  • the Mobile stations that do not support the VGCS conversation shall ignore the HANDOVER COMMAND message if the target mode VGCS information element is included in the message and send a RR STATUS message with specified cause to the network. If on the contrary the above mentioned information element and an additional information element to define a ciphering node are included in the same message, then a Mobile unit supporting the VGCS conversation shall consider the HANDOVER COMMAND message as wrong and immediately send back a
  • ACCESS message in the new cell are made in the case of Handover Intercell among non synchronised cells, but could be made also for synchronous cells to optimize access time and power parameters.
  • the network in the HANDOVER COMMAND message signals which one of the two procedures must be enabled.
  • the Mobile after receipt of the HANDOVER COMMAND message, starts sending the sequence SYNC1 on the UpPTS channel of the cell indicated.
  • the Mobile starts a Timer T3124 setting the starting point of the count at the time slot where the burst SYNC1 has been sent for the first time to a UpPTS. If the HANDOVER COMMAND message indicates more than one SYNC1 sequence allowed, the Mobile unit randomly selects a SYNC1 sequence among the allowed ones. In case of synchronous handover the Timer 3124 is started setting the starting point of the count at the time slot in which the HANDOVER ACCESS message has been sent for the first time on the main link DCCH.
  • the network obtains the necessary characteristics RF from the SYNC1 burst, and sends a PHYSICAL INFORMATION message on the relevant P-FACH channel carried by the adjacent frame in "unacknowledged" mode.
  • the Mobile after having sent the first burst SYNC1 , starts monitoring the
  • P-FACH channel indicated to reveal the PHYSICAL INFORMATION message.
  • This message shall include the reference number of the signature used by the Mobile, a frame number relevant (see note), to that in which the SYNC1 acknowledged burst (acknowledged) has been received, the interference level on the corresponding P-RACH, and the Timing advance.
  • the PHYSICAL INFORMATION message is waited for within 4 frames from the transmission of SYNC1. In case no valid response is revealed, the above mentioned procedure shall be repeated until the count of Timer T3124 expires.
  • the above-mentioned relative system frame number has no connection with the absolute frame number in force in the cell, otherwise the technical problem would not arise, but on the contrary it is a number that indicates to the Mobile a distance between the reception frame of the PHYSICAL INFORMATION and the emission frame of the SYNC1 which the same refer to. This distance helps the Mobile to understand if the reply of the network is addressed to it.
  • the Mobile receives a PHYSICAL INFORMATION message it stops sending the SYNC1 bursts and starts recurrently sending the HANDOVER ACCESS message in successive frames on the Main Signalling Link DCCH. This message is sent on single burst in no-ciphering mode.
  • Ciphering/deciphering cannot start because the Mobile does not know yet the frame number SFN of the new channel in the destination cell.
  • the problem can be understood comparing Level 1 of the downlink synchronization mechanism of the 3G system with the GSM one.
  • the downlink pilot DwPTS does not include the frame number SFN, which shall be initially acquired by the P-CCPCH channel (in this case BCCH). Therefore the Mobile after having sent the first HANDOVER ACCESS message, and in lack of the means not supplied by the present invention, should start monitoring the BCCH to detect the System Information and acquire the frame number SFN.
  • the times of the above mentioned message is of one for each 240 ms signalling multiframe: a time decidedly prohibitive for the handover.
  • the network enables the main link DCCH in reception mode.
  • the network receives the HANDOVER ACCESS message, it transmits to the Mobile unit, in "unacknowledged" mode on the main link DCCH an appropriate FRAME NUMBER INFORMATION message containing the information on the system frame number SFN, using to this purpose a coding scheme operating on the single burst and enabling the reception to use a decoding scheme requested by the service. If applicable, deciphering is started immediately.
  • the message contains the following information:
  • the network repeats the transmission of the FRAME NUMBER INFORMATION message in subsequent Level 1 frames, up to reception of a TCH frame sent by the
  • the correct decoding of a frame means that the deciphering algorithm and error detection tests, if any, indicate absence oi errors.
  • the network When the network receives from the Mobile unit a control frame or a TCH frame, correctly decoded, it stops the transmission of the FRAME NUMBER INFORMATION message and enables the transmission using the coding scheme requested by the service. When applicable, ciphering starts immediately.
  • the Mobile unit receives the FRAME NUMBER INFORMATION message, it stops the Timer T3124; it stops sending the HANDOVER ACCESS message, it enables the physical channel in transmission and reception mode, using the coding/decoding scheme requested by the service, and if necessary it connects the channels. When applicable the ciphering/deciphering immediately starts. When the connections at the lower Level have been successfully established the
  • Timer T3103 releases the old channels of the old cell together with the signatures possibly destined to the handover procedure.
  • the mobile unit whenever requested to do this in the HANDOVER COMMAND message, includes in the HANDOVER COMPLETE message the time difference at the synchronization instant measured at handover processing, corrected by one half of the synchronization advance (timing advance parameter).
  • Irregular cases can occur in the handover procedure, and in these cases the
  • HANDOVER FAILURE message with the cause "handover impossible, timing advance out of range” and makes no attempt to process the handover. • If the HANDOVER COMMAND message instructs the Mobile unit to use a Channel Description or a Mode not supported, or if the Channel Mode is not defined for all the channel sets, then the Mobile returns a HANDOVER FAILURE message with the cause "channel mode unacceptable" and remains in the current channel(s) using the old Mode.
  • the Mobile unit If the HANDOVER COMMAND message instructs the Mobile unit to use a frequency not supported, then the Mobile returns a HANDOVER FAILURE message with the cause "frequency not supported" and remains in the current channel(s). • On the Mobile unit side, if the count of Timer 3124 expires or if a failure occurs on the new channel at the Lower level before the HANDOVER COMPLETE message has been sent, the Mobile unit disables the new channels, enables the old channels again, reconnects the TCH channels if any, and starts the establishment of the main signalling link. The Mobile sends a HANDOVER FAILURE message on the main signalling link and retrieves the normal operation as the handover attempt had not taken place. The operation parameters (the ciphering node for instance) on return of the old channel are still those applied before the reception of the HANDOVER COMMAND message.

Abstract

L'invention concerne un procédé de transfert intercellulaire dans des systèmes mobiles SUTM dans la technique AMRT-SCDMA (et aussi FDMS-SDMA) à duplexage intégral du type DRT. La complexité de la technique adoptée requiert un mécanisme de synchronisation de trame utilisant un signal pilote en liaison descendante émis par radiodiffusion par la station de base, auquel des séquences de signature émises par des unités mobiles uniques font écho dans les procédures prévoyant un accès en liaison montante. Ceci, associé à la vitesse élevée de chiffrement (1,28 Mchip) imposée par la technique AMCR, empêche l'ajout d'autres champs à la séquence du pilote en liaison descendante, qui doit rester une séquence de synchronisation pure. A la différence du GSM, un champ va faire défaut dans la salve de synchronisation servant au transport du numéro de trame du système FSN, indispensable à la synchronisation de l'hypertrame et le début du chiffrement sur le canal. L'information sur le nombre de trames du système (SFN) est comprise dans le canal commun de signalisation ainsi que les autres informations de radiodiffusion. Ceci ralentirait de façon inacceptable le transfert, c'est pourquoi un message a été créé et mis à disposition du réseau, afin de remettre le numéro de trame du système FSN actuel dans la nouvelle cellule de manière spécifique, en réponse au message d'accès de transfert envoyé par le téléphone mobile (fig.16).
EP00917263A 2000-03-23 2000-03-23 Procedures de transfert dans un systeme de radiocommunication Withdrawn EP1281289A1 (fr)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN100388820C (zh) * 2005-09-28 2008-05-14 华为技术有限公司 集群呼叫业务控制方法以及应用该方法的终端设备和系统
CN105120489A (zh) * 2011-10-24 2015-12-02 联发科技股份有限公司 邻近小区监测方法

Families Citing this family (91)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10023826B4 (de) * 2000-05-15 2015-07-09 Qualcomm Incorporated Verfahren zum Übertragen einer Rahmennummer in einem Kommunikationssystem
FI110736B (fi) * 2000-08-01 2003-03-14 Nokia Corp Datansiirtomenetelmä, tilaajapäätelaite ja GPRS/EDGE-radioliityntäverkko
GB0200091D0 (en) * 2002-01-04 2002-02-20 Roke Manor Research Scheduling algorithm for nodeb steady state sync
CN100508474C (zh) * 2002-02-10 2009-07-01 华为技术有限公司 无线局域网中移动终端在接入点间切换的方法
CN1200590C (zh) * 2002-03-01 2005-05-04 华为技术有限公司 一种实现gsm与cdma网络信令互通的方法
CN1663300A (zh) * 2002-04-29 2005-08-31 诺基亚有限公司 无线通信系统中用户设备连接的切换
CA2506511A1 (fr) * 2002-11-19 2004-06-03 Tenxc Wireless Inc. Systeme hybride de formation de faisceau en diversite spatio-temporelle
CN1157969C (zh) * 2002-12-13 2004-07-14 大唐移动通信设备有限公司 一种移动通信系统中的切换方法
CN100334848C (zh) * 2003-01-28 2007-08-29 华为技术有限公司 一种控制用户终端在不同网络间切换的实现方法
JP4225087B2 (ja) * 2003-03-19 2009-02-18 日本電気株式会社 移動通信システム、無線基地局制御装置及びそれらに用いるアウタループ電力制御方法
KR100689508B1 (ko) * 2003-09-04 2007-03-02 삼성전자주식회사 통신 시스템에서 핸드오버 수행 방법
US9226308B2 (en) 2003-10-15 2015-12-29 Qualcomm Incorporated Method, apparatus, and system for medium access control
US8462817B2 (en) 2003-10-15 2013-06-11 Qualcomm Incorporated Method, apparatus, and system for multiplexing protocol data units
US8472473B2 (en) 2003-10-15 2013-06-25 Qualcomm Incorporated Wireless LAN protocol stack
US8233462B2 (en) 2003-10-15 2012-07-31 Qualcomm Incorporated High speed media access control and direct link protocol
US8284752B2 (en) 2003-10-15 2012-10-09 Qualcomm Incorporated Method, apparatus, and system for medium access control
US8483105B2 (en) 2003-10-15 2013-07-09 Qualcomm Incorporated High speed media access control
US8903440B2 (en) 2004-01-29 2014-12-02 Qualcomm Incorporated Distributed hierarchical scheduling in an ad hoc network
KR100827105B1 (ko) * 2004-02-13 2008-05-02 삼성전자주식회사 광대역 무선 통신 시스템에서 고속 레인징을 통한 빠른핸드오버 수행 방법 및 장치
KR100612675B1 (ko) 2004-03-10 2006-08-14 에스케이 텔레콤주식회사 비동기망과 동기망이 혼재된 이동통신 시스템에서 묵음구간을 최소화하기 위한 상호연동 운용부 및 교환기간메시지 전송 프로토콜을 이용한 이동통신 단말의 핸드오버방법
US8315271B2 (en) 2004-03-26 2012-11-20 Qualcomm Incorporated Method and apparatus for an ad-hoc wireless communications system
US7564814B2 (en) 2004-05-07 2009-07-21 Qualcomm, Incorporated Transmission mode and rate selection for a wireless communication system
CN100393031C (zh) * 2004-05-27 2008-06-04 中兴通讯股份有限公司 无线资源控制层中加密激活点的确定方法
US8401018B2 (en) 2004-06-02 2013-03-19 Qualcomm Incorporated Method and apparatus for scheduling in a wireless network
EP1757135A1 (fr) * 2004-06-15 2007-02-28 TELEFONAKTIEBOLAGET LM ERICSSON (publ) Procede de transfert avec coupure en douceur, station mobile et station de base adaptees au procede
WO2006015524A1 (fr) * 2004-08-13 2006-02-16 Shunde Xinbao Electrical Equipments Co., Ltd. Foshan City Generateur de vapeur et percolateur double fonction qui l’emploie
US8086241B2 (en) * 2004-11-18 2011-12-27 Mediatek Incorporation Handoff methods, and devices utilizing same
RU2396711C2 (ru) 2005-01-06 2010-08-10 Эл Джи Электроникс Инк. Улучшения системы высокоскоростной пакетной передачи данных по восходящей линии связи
CN100393172C (zh) * 2005-01-19 2008-06-04 中兴通讯股份有限公司 个人手持电话系统手机无缝切换的方法
CN1747598B (zh) * 2005-08-12 2010-11-03 上海宣普实业有限公司 硬切换的方法和设备以及使用该方法和该设备的td-scdma系统
US8855704B2 (en) 2005-08-26 2014-10-07 Qualcomm Incorporated Fast cell selection in TD-CDMA (UMTS TDD)
US8600336B2 (en) 2005-09-12 2013-12-03 Qualcomm Incorporated Scheduling with reverse direction grant in wireless communication systems
US8068464B2 (en) 2005-10-27 2011-11-29 Qualcomm Incorporated Varying scrambling/OVSF codes within a TD-CDMA slot to overcome jamming effect by a dominant interferer
US8130727B2 (en) 2005-10-27 2012-03-06 Qualcomm Incorporated Quasi-orthogonal allocation of codes in TD-CDMA systems
TW200729990A (en) * 2005-12-22 2007-08-01 Interdigital Tech Corp Method and system for adjusting uplink transmission timing immediately for long term evolution handover
WO2007124677A1 (fr) * 2006-04-21 2007-11-08 Huawei Technologies Co., Ltd. Procédé et dispositif pour commande de commutateur
WO2007126100A1 (fr) * 2006-05-02 2007-11-08 Ntt Docomo, Inc. Terminal mobile et système de communication mobile
JP4265620B2 (ja) * 2006-05-26 2009-05-20 沖電気工業株式会社 アクセス制御装置、無線装置、ネットワーク、アクセス制御方法及びアクセス制御プログラム
GB0611343D0 (en) * 2006-06-09 2006-07-19 Roke Manor Research Method of handover of packet switched resources
CN100454819C (zh) 2006-06-19 2009-01-21 华为技术有限公司 一种多播服务实现方法
KR101596188B1 (ko) 2006-06-20 2016-02-19 인터디지탈 테크날러지 코포레이션 무선 통신 시스템에서의 핸드오버를 수행하기 위한 방법 및 시스템
CN101110633B (zh) * 2006-07-19 2011-08-31 电信科学技术研究院 Gsm系统与td-scdma系统初始同步的方法及装置
CN101111055B (zh) * 2006-07-21 2010-09-29 华为技术有限公司 控制切换执行的方法、终端
CN1889785B (zh) * 2006-07-27 2010-05-12 华为技术有限公司 分组切换过程中对切换失败进行处理的方法、系统和网络
JP5125027B2 (ja) * 2006-08-17 2013-01-23 富士通株式会社 無線通信システムにおける無線中継通信方法並びに無線基地局及び無線中継局
TWI354465B (en) * 2006-08-21 2011-12-11 Qualcomm Inc Method and apparatus for flexible pilot pattern
CN101162918B (zh) * 2006-10-09 2010-09-15 北京信威通信技术股份有限公司 Scdma系统接入试探序列的第三个符号的检测方法及系统
GB2443236B (en) * 2006-10-27 2009-03-25 Motorola Inc A cellular communication system
EP2958393B1 (fr) * 2006-11-01 2018-02-07 Telefonaktiebolaget LM Ericsson (publ) Distribution de données de diffusion/multidiffusion dans des systèmes de télécommunications
CN101179844B (zh) * 2006-11-06 2011-07-20 华为技术有限公司 分组切换取消的处理、分组切换方法
WO2008096317A1 (fr) * 2007-02-05 2008-08-14 Nokia Corporation Système et procédé pour fournir une transmission de numéro de trame système (sfn) dédiée dans un transfert
CN101267593B (zh) * 2007-03-15 2011-04-20 华为技术有限公司 对目标小区进行组播广播多媒体业务激活的方法及基站
EP2007033A1 (fr) * 2007-06-19 2008-12-24 Motorola, Inc. Système et procédé pour la synchronisation d'un dispositif GSM
CN101351009B (zh) * 2007-07-19 2011-07-06 展讯通信（上海）有限公司 高可靠性快速相关控制信道/半速率检测方法
CN101365224B (zh) * 2007-08-07 2011-09-07 鼎桥通信技术有限公司 减小相邻小区干扰的方法和装置
CN101136777B (zh) * 2007-10-18 2010-06-23 网经科技（苏州）有限公司 网络管理系统中双加密通道协作的安全管理方法
US9544828B2 (en) 2007-12-05 2017-01-10 Qualcomm Incorporated Handover failure procedures in communication systems
CN101897130A (zh) * 2007-12-12 2010-11-24 艾利森电话股份有限公司 改进的广播信道
GB0724435D0 (en) * 2007-12-14 2008-01-30 Icera Inc Physical channel establishment
CN101500189B (zh) * 2008-02-03 2011-06-01 华为技术有限公司 实现系统信息调度的方法、系统及终端
WO2009111233A1 (fr) 2008-03-04 2009-09-11 Interdigital Patent Holdings, Inc. Procédé et appareil pour accéder à un canal d’accès aléatoire en utilisant sélectivement des préambules dédiés ou basés sur une contention au cours d'un transfert
US8712415B2 (en) * 2008-03-20 2014-04-29 Interdigital Patent Holdings, Inc. Timing and cell specific system information handling for handover in evolved UTRA
US8570977B2 (en) * 2008-03-24 2013-10-29 Qualcomm Incorporated Method and apparatus for handover in a wireless communication system
CN101594175B (zh) * 2008-05-27 2012-12-26 电信科学技术研究院 一种波束赋型传输的方法、系统及装置
EP2308258B1 (fr) 2008-06-30 2017-12-06 InterDigital Patent Holdings, Inc. Procédé et dispositif pour effectuer un transfert dans un réseau à accès radio terrestre universel évolué
CN101742518B (zh) * 2008-11-06 2013-04-17 华为技术有限公司 一种定时调整方法、系统和装置
CN101835228B (zh) * 2009-03-09 2014-01-01 中兴通讯股份有限公司 一种保持反向逻辑信道一致的方法及系统
WO2011037654A1 (fr) * 2009-09-22 2011-03-31 Qualcomm Incorporated Procédé et appareil destinés à la synchronisation de numéro de trame système dans des réseaux d'accès multiple par répartition en code synchrone et répartition dans le temps (td-scdma)
WO2011040991A1 (fr) * 2009-09-29 2011-04-07 Qualcomm Incorporated Procédé et appareil de reprise sur défaillance de liaison durant un transfert dans des systèmes td-scdma
WO2011056259A1 (fr) * 2009-11-03 2011-05-12 Qualcomm Incorporated Procede et appareil pour poursuivre l'acces par paquets a haut debit lors du transfert de temoin dans des systemes amdcs rt
WO2011059524A1 (fr) * 2009-11-10 2011-05-19 Qualcomm Incorporated Procédé et appareil permettant de supporter une opération ack/cqi d'accès hsdpa pendant un transfert intercellulaire de type bâton dans des systèmes td-scdma
JP5627899B2 (ja) * 2010-02-08 2014-11-19 京セラ株式会社 基地局及び基地局の通信方法
CN102196511A (zh) * 2010-03-15 2011-09-21 中国移动通信集团公司 小区参数优化的方法、系统及设备
CN102487547B (zh) * 2010-12-01 2014-12-03 华为技术有限公司 信道资源分配方法、装置及终端
US9226213B2 (en) * 2012-02-23 2015-12-29 Qualcomm Incorporated Enhanced slow associated control channel (ESACCH)
CN103369606B (zh) * 2012-04-09 2018-09-25 南京中兴软件有限责任公司 用于gsm终端分组交换域切换的方法和系统
KR20130124004A (ko) * 2012-05-04 2013-11-13 삼성전자주식회사 밀리미터 전파 통신 시스템에서 전송기법에 따른 자원할당 방법 및 장치
CN111586783B (zh) 2012-12-10 2022-07-19 索尼公司 管理设备、通信设备、运动估计设备、系统、方法和介质
CN104168640A (zh) * 2013-05-17 2014-11-26 中兴通讯股份有限公司 一种接收端pdcp层hfn失步的恢复方法和设备
GB2516886A (en) 2013-08-02 2015-02-11 Nec Corp Communications system
US11153875B2 (en) 2014-05-19 2021-10-19 Qualcomm Incorporated Apparatus and method for inter-band pairing of carriers for time division duplex transmit- and receive-switching and its application to multiplexing of different transmission time intervals
US11432305B2 (en) 2014-05-19 2022-08-30 Qualcomm Incorporated Apparatus and method for synchronous multiplexing and multiple access for different latency targets utilizing thin control
US9264887B2 (en) * 2014-06-20 2016-02-16 Qualcomm Incorporated Systems and methods for enhanced system information decoding
EP3291491B1 (fr) * 2015-05-15 2020-01-08 Huawei Technologies Co., Ltd. Procédé et appareil de traitement de signal
WO2017058308A2 (fr) * 2015-06-17 2017-04-06 Hughes Network Systems, Llc Procédé d'acquisition de signaux d'accès multiple basé sur un mot unique (uw)
EP3253117B1 (fr) * 2016-06-03 2021-02-17 HTC Corporation Gestion de transfert
FR3088792A1 (fr) * 2018-11-19 2020-05-22 Orange Gestion de transfert intercellulaire sans latence pour terminal mobile à attachement multiple
CN113630860B (zh) * 2020-05-06 2023-11-24 北京佰才邦技术股份有限公司 一种信息确认方法、终端设备及网络设备
CN112598895B (zh) * 2020-11-16 2023-05-19 中国电力科学研究院有限公司 一种用于防止检定电能表时多信道冲突的系统及方法
CN113890592B (zh) * 2021-10-27 2022-05-24 广州爱浦路网络技术有限公司 通信卫星切换方法、天地一体化信息网络系统、装置和介质
CN114070383B (zh) * 2021-11-18 2023-06-27 东方红卫星移动通信有限公司 一种低轨卫星通信系统中提升频谱效率的通信方法及装置

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6094575A (en) * 1993-11-01 2000-07-25 Omnipoint Corporation Communication system and method
JP3479935B2 (ja) * 1998-08-19 2003-12-15 富士通株式会社 Ｃｄｍａ移動通信におけるハンドオーバ方法並びにｃｄｍａ移動通信システム、その基地局及び移動局
FI106494B (fi) * 1998-11-05 2001-02-15 Nokia Networks Oy Kehystahdistusmekanismi
FI107487B (fi) * 1999-03-08 2001-08-15 Nokia Mobile Phones Ltd Datalähetyksen salausmenetelmä radiojärjestelmässä

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO0172081A1 *

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN100388820C (zh) * 2005-09-28 2008-05-14 华为技术有限公司 集群呼叫业务控制方法以及应用该方法的终端设备和系统
CN105120489A (zh) * 2011-10-24 2015-12-02 联发科技股份有限公司 邻近小区监测方法
CN105120489B (zh) * 2011-10-24 2019-02-05 联发科技股份有限公司 邻近小区监测方法

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WO2001072081A1 (fr) 2001-09-27
CN1451250A (zh) 2003-10-22
JP2003528507A (ja) 2003-09-24

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