CN100377540C - Method for multi-carrier frequency system access - Google Patents

Abstract

A method for accessing a multi-carrier frequency system, applied to a multi-carrier frequency system including user equipment, comprising: the system determines a fast access physical channel and a random access physical channel on a primary carrier frequency and an uplink channel on a secondary carrier frequency The association relationship of the pilot channel; configure the quick access physical channel and the random access physical channel on the main carrier frequency according to the association relationship; the user equipment sends the uplink synchronization code on the uplink pilot channel of the auxiliary carrier frequency; through the main carrier frequency The fast access physical channel on the main carrier frequency receives the information fed back by the system, and sends an access message on the random access physical channel of the corresponding main carrier frequency according to the confirmation information, and completes the system access. It can solve the technical problems of collision and blocking caused by insufficient access resources due to the access of more new users, and the technical problems of multi-carrier inter-frequency interference in the same cell due to the use of common downlink channels without power control in multiple secondary carrier frequencies ; The method can facilitate wireless resource management, and further improve the access performance of a multi-carrier frequency system.

Description

Method for multi-carrier frequency system access

technical field

The invention relates to the communication field, in particular to a method for accessing a multi-carrier frequency system.

Background technique

Time Division Synchronize Multiple Access (TD-SCDMA), in the International Telecommunication Union (ITU) standard, is called a low chip rate (1.28MCps, 1.28 Mchip/s) time division multiplexing technical solution. The TD-SCDMA system has a large capacity, so the number of sites required to build network coverage is less than that of the GSM system, and it also reduces the investment in network construction. Therefore, it is widely used in the communication field as a typical multi-carrier frequency system.

In the current TD-SCDMA system, there is a method of using the main carrier frequency plus several auxiliary carrier frequencies to achieve multi-carrier frequency cell coverage to achieve multi-carrier frequency system access. However, this method cannot solve the problem due to The access of more new users leads to collisions and congestion caused by insufficient access resources; thus, an Uplink Pilot Channel (Uplink Pilot Channel, UpPCH) is configured on multiple carrier frequencies to achieve multi-carrier frequency system access, but This method fails to solve the technical problem of interference between multiple carrier frequencies in the same cell due to the use of common downlink channels without power control in multiple auxiliary carrier frequencies. Therefore, in order to ensure the communication quality of the majority of user equipment, the multi-carrier frequency system Access performance has become an urgent need for people.

In the Time Division Synchronize Multiple Access (TD-SCDMA) multi-carrier frequency system of prior art 1, a method of adding one main carrier frequency and several auxiliary carrier frequencies is used to realize multi-carrier frequency cell coverage. As shown in Figure 1, it is the frequency point configuration of the coverage area of the base station in the prior art 1. It can be seen from the figure that a common control channel and a dedicated channel (possibly included) are configured in the main frequency point, and in the secondary frequency point 1 , Auxiliary frequency point 2...Auxiliary frequency point N is only configured with a dedicated channel.

In the same cell, the base station NodeB only sends the downlink pilot time slot (Downlink Pilot Time Slot, DwPTS) and the broadcast information fixed on the first and second code channels of TS0 on the main carrier frequency. At the same time, common control channels, such as the second common control physical channel (Secondary Common Control Channel, SCCPCH), paging indicator channel (Paging Indicator Channel, PICH), random access physical channel (Physical Random Access Channel, PRACH), uplink pilot channel ( Uplink Pilot Channel (UpPCH) and Fast Physical Access Channel (FPACH) are configured on the main carrier frequency.

In prior art 1, only the main frequency point has a common control channel, so only the main frequency point has access resources UpPTS, FPACH, and PRACH channels. Since the uplink pilot channel (Uplink Pilot Channel, UpPCH) is configured on the main carrier frequency, the uplink pilot channel (Uplink Pilot Channel, UpPCH) is not configured on the auxiliary carrier frequency. All UEs in the cell randomly access the network through the uplink pilot channel (UplinkPilot Channel, UpPCH) of the main carrier frequency to receive.

The second prior art is to configure an uplink pilot channel (Uplink Pilot Channel, UpPCH) on m carrier frequencies for a multi-carrier frequency cell with N carrier frequencies, where 1<=m<=N, as shown in Figure 2 As shown, the main frequency point is configured with a public control channel and a dedicated channel (possibly included), and the secondary frequency point 1 is configured with a dedicated channel, configured with an uplink pilot channel (Uplink Pilot Channel, UpPCH), and an uplink pilot channel (Uplink Pilot Channel) Channel, UpPCH) interrelated fast access physical channel (Fast Physical Access Channel, FPACH) and random access physical channel (PhysicalRandom Access Channel, PRACH).

The uplink pilot channel (Uplink Pilot Channel, UpPCH) must be configured on the main carrier frequency, and the uplink pilot channel (Uplink Pilot Channel, UpPCH) can be configured on the auxiliary carrier frequency. The specific configuration is flexible and not limited. For example, UpPCH can be configured on all auxiliary carrier frequencies, and UpPCH can also be configured on some auxiliary carrier frequencies; 8 codes can be configured on a certain auxiliary carrier frequency, or only some codes can be configured.

The interrelated uplink pilot channel (Uplink Pilot Channel, UpPCH), fast access physical channel (Fast Physical Access Channel, FPACH) and random access physical channel (Physical Random Access Channel, PRACH) are limited to the same carrier frequency. The signature of the same carrier frequency is associated with the Fast Physical Access Channel (FPACH) of the same carrier frequency; the Fast Physical Access Channel (FPACH) of the same carrier frequency and the random access physical channel of the same carrier frequency Channel (Physical Random Access Channel, PRACH) association. For example, 8 SYNC-UL codes are 0, 1, 2, 3, 4, 5, 6, 7; 2 FPACHs are FPACH0 and FPACH1; 3 PRACHs are PRACH0, PRACH1 and PRACH3. They can be divided into two association combinations, as shown in Figure 3. In association relationship 1, SYNC-UL codes are 0, 1, 2, 3, FPACH is 0, PRACH is 0, 1; association relationship 2 Among them, the SYNC-UL codes are 4, 5, 6, and 7, the FPACH is 1, and the PRACH is 3.

When UE selects the SYNC-UL code in association combination 1, UTRAN can only perform feedback through FPACH0. Which PRACH channel to use can be determined according to its feedback time. When the FPACH feedback time is the subsequent even subframe (2, 4, 6) of the SYNC-UL transmission subframe, the UE will use PRACH0 to send the access message. When the FPACH feedback The time is when the subsequent odd subframes (1, 3, 5) of the SYNC-UL transmission subframe, the UE will use PRACH1 to send the access message. It can be seen that when the uplink synchronization code (Synchronization-Uplink, SYNC-UL) sequence is sent, the UE knows the Fast Physical Access Channel (FPACH) resource used for access, and randomly accesses the physical channel (Physical Random Access Channel, PRACH) resources.

When accessing the uplink FPACH, the user UE randomly selects the uplink pilot channel (Uplink Pilot Channel, UpPCH) on the main carrier frequency to access, or the uplink pilot channel (Uplink Pilot Channel, UpPCH) on the auxiliary carrier frequency to access; It is also possible to distribute the users who need to access to different carrier frequencies as uniformly as possible through the hash function. In this way, since the user has a selective choice when accessing the uplink frequency channel, or evenly distributes the users, the conflict is reduced. However, in order that the farthest user terminal in the cell or the user terminal with the worst signal quality can still receive the FPACH, the downlink FPACH does not have power control, but is transmitted with a higher power, which is likely to cause interference to adjacent carrier frequencies.

Based on the analysis of the random access method of the above-mentioned multi-carrier frequency access system, it can be concluded that the existing technology has the following deficiencies:

Existing technology 1. In the case of multiple carrier frequencies (assuming N carrier frequencies), there are (N-1) secondary carrier frequencies in the cell. Usually, the number of users supported by N carrier frequencies will be N times that in the case of single carrier frequency . Since the uplink pilot time slot (Uplink Pilot Time Slot, UpPTS) is configured on the main carrier frequency, all UEs in the cell must randomly access the network through the uplink pilot time slot (Uplink Pilot Time Slot, UpPTS) of the main carrier frequency . After the number of users doubles, there is no increase in the uplink pilot time slot (Uplink PilotTime Slot, UpPTS) of access resources, and there are still 8 uplink synchronization codes (Synchronization-Uplink, SYNC-UL) on the main carrier frequency. It is easy to cause collision and obstruction of access.

The prior art two multi-carrier frequency random access method, although it can reduce the generation of collision and blocking when multi-user access, but the fast access physical channel (Fast access physical channel) of the common downlink channel without power control is used in multiple auxiliary carrier frequencies. Physical Access Channel, FPACH), will inevitably lead to increased interference between common downlink channel carrier frequencies.

Contents of the invention

In order to solve the collision and blocking caused by insufficient access resources in the prior art 1 and the technical problem of interference between multiple carrier frequencies in the same cell in the prior art 2, the present invention provides a method for improving the access performance of a multi-carrier frequency system. In order to improve the performance of multi-carrier frequency system access.

In order to solve the above problems, the present invention provides a method for improving the access performance of a multi-carrier frequency system. The method is applied to a multi-carrier frequency system including user equipment, which includes:

A. The system determines the relationship between the fast access physical channel and the random access physical channel on the main carrier frequency and the pre-configured uplink pilot channel on the auxiliary carrier frequency;

B. Configuring a quick access physical channel and a random access physical channel on the main carrier frequency according to the association relationship;

C. The user equipment obtains access resource configuration and associated information according to the main carrier frequency broadcast; the user equipment sends the uplink synchronization code on the uplink pilot channel of the auxiliary carrier frequency;

D. Receive the information fed back by the system through the fast access physical channel on the main carrier frequency, and send an access message on the corresponding random access physical channel of the main carrier frequency according to the confirmation information, and complete the system access.

Among them, between steps C and D, it also includes: the system judges whether the uplink synchronization code of the auxiliary carrier frequency is the same as the uplink synchronization code of the main carrier frequency. broadcast the uplink synchronization code of the secondary carrier frequency to the user terminal.

The step D further includes: judging whether the feedback information is received on the fast access physical channel on the main carrier frequency, and if so, sending an access message on the corresponding random access physical channel on the main carrier frequency; otherwise, waiting After a period of time, return to step D.

The method further includes: establishing an association relationship table in the system for storing the association relationship between the fast access physical channel and the random access physical channel on the main carrier frequency and the uplink pilot channel on the auxiliary carrier frequency.

Wherein, before returning to step D, it further includes: the user equipment readjusts the transmission time and transmission power.

Wherein, before the sending of the access message, it further includes: the user equipment adjusts the transmission time and transmission power.

Wherein the uplink pilot channel on the auxiliary carrier frequency is configured with 8 or less than 8 uplink synchronization codes.

Compared with the prior art, the present invention has the following beneficial effects: firstly, when the number of users in the cell increases by using the access resource Uplink Pilot Time Slot (UpPTS) of the auxiliary carrier frequency, Access resources, such as Uplink Pilot Channel (Uplink PilotChannel, UpPCH), Fast Physical Access Channel (Fast Physical Access Channel, FPACH), PRACH) can also be increased accordingly, thereby avoiding the lack of access resources in the prior art. collisions and obstructions. Secondly, because the random access physical channel (PhysicalRandom Access Channel, PRACH) and the fast physical access channel (Fast PhysicalAccess Channel, FPACH) are limited to the main carrier frequency, so that the fast access physical channel of the public downlink channel without power control The channel (Fast Physical Access Channel, FPACH) is limited to the main carrier frequency, which reduces the inter-carrier interference; since the random access physical channel (Physical Random Access Channel, PRACH) is limited to the main carrier frequency, except for the uplink pilot slot (Uplink Pilot Time Slot (UpPTS), other uplink channel time slots on the auxiliary carrier frequency can be allocated as dedicated resources, so as to facilitate wireless resource management and improve multi-carrier frequency system access performance.

Description of drawings

FIG. 1 is a frequency configuration diagram of a cell at the same location in prior art 1;

FIG. 2 is a frequency point configuration diagram of cells at the same location in prior art 2;

FIG. 3 is a correlation table of SYNC-UL, FPACH and PRACH in prior art 1;

Fig. 4 is a TD-SCDMA frame structure diagram;

Fig. 5 is the frequency configuration diagram of the same location cell in the present invention;

Fig. 6 is the correlation table of SYNC-UL, FPACH and PRACH among the present invention;

Fig. 7 is a flowchart of the present invention;

The English abbreviations in Figure 4 mean:

ms: milliseconds;

us: microseconds;

TS: time slot (Time Slot, TS);

DwPTS: Downlink Pilot Time Slot (DwPTS); also known as Downlink Pilot CHannel (DwPCH); UpPTS: Uplink Pilot Time Slot (UpPTS); also known as , uplink pilot channel (UplinkPilot Channel, UpPCH);

GP: guard interval.

Detailed ways

As shown in Figure 4, in terms of time, a Time Division Synchronize Multiple Access (TD-SCDMA) signal is divided into a period and a period of time units. A basic time unit is called "radio frame", and the time length of each radio frame is 10ms (milliseconds). Each radio frame is divided into two "subframes" of equal duration, and the duration of each subframe is 5ms. Each subframe is divided into several different parts, among which there are 7 time slots (Time Slot, TS) with the same time length, and the position is between the 0th time slot (TS0) and the 1st time slot (TS1). The downlink pilot time slot (Downlink Pilot Time Slot, DwPTS), the uplink pilot time slot (Uplink Pilot Time Slot, UpPTS) and a guard interval (GP).

According to different signal directions, each time slot is divided into two types: uplink direction and downlink direction. The uplink direction means that the wireless signal transmitted during the time slot is transmitted by the UE and received by the NodeB; the downlink direction means that the wireless signal transmitted during the time slot is transmitted by the NodeB and received by the UE.

In the Time Division Synchronize Multiple Access (TD-SCDMA) standard, TS0 is always designated as the downlink direction, and TS1 is always designated as the uplink direction. TS2, TS3, ..., TS6 will be dynamically designated as uplink or downlink according to service requirements. In addition, the downlink pilot time slot (Downlink Pilot Time Slot, DwPTS) is the downlink direction, and the uplink pilot time slot (Uplink Pilot Time Slot, UpPTS) is the uplink direction. The time slots in the uplink direction and the time slots in the downlink direction are separated by a switching point.

In the technical solution of the present invention, for a multi-carrier cell with N carrier frequencies, uplink pilot channels (Uplink Pilot Channel, UpPCH) can be configured on m carrier frequencies, wherein 1<=m<=N. Among the m carrier frequencies, because there is no difference between the carrier frequencies, one carrier frequency can be randomly designated as the main carrier frequency, and the rest are designated as auxiliary carrier frequencies. As shown in Figure 5, the common control channel is configured on the main carrier frequency, and it can also contain dedicated channels, that is, the uplink pilot channel (Uplink PilotChannel, UpPCH) must be configured on the main carrier frequency; for the auxiliary carrier frequency, it can be configured according to the system configuration requirements. Flexible configuration of uplink pilot channel (Uplink Pilot Channel, UpPCH). For example, UpPCH can be configured on all auxiliary carrier frequencies, and UpPCH can also be configured on some auxiliary carrier frequencies; 8 codes can be configured on a certain auxiliary carrier frequency. You can also configure only part of the code.

In the present invention, a fast physical access channel (Fast Physical Access Channel, FPACH) and a random access physical channel (Physical Random Access Channel, PRACH) are related to each other. The relationship between the two is shown in Figure 6. The eight SYNC-UL codes on the main carrier frequency, auxiliary carrier frequency 1 and auxiliary carrier frequency 2 are 0, 1, 2, 3, 4, 5, 6, and 7 respectively; 5 FPACHs, FPACH0, FPACH1, FPACH2, FPACH3, FPACH4; 7 PRACHs, PRACH0, PRACH1, PRACH3, PRACH4, PRACH5, PRACH6. They can be divided into 5 association combinations, association combination 1, that is, SYNC-UL 0, 1, 2, 3 located on the main carrier frequency corresponds to FPACH 0 of the main carrier frequency and PRACH 0, 1 of the main carrier frequency; association combination 2 , that is, SYNC-UL 4, 5, 6, 7 on the main carrier frequency corresponds to FPACH 1 on the main carrier frequency and PRACH 2 on the main carrier frequency; association combination 3, that is, SYNC-UL 0, 1 on the auxiliary carrier frequency 1 , 2, 3 correspond to the FPACH 2 of the main carrier frequency and the PRACH 3 of the main carrier frequency; the association combination 4, that is, the SYNC-UL 4, 5, 6, 7 located at the auxiliary carrier frequency 1 and the FPACH 3 of the main carrier frequency and the main The PRACH 4 of the carrier frequency corresponds; the association combination 5, that is, the SYNC-UL 0, 1, 2, 3 located in the auxiliary carrier frequency 2 corresponds to the FPACH 4 of the main carrier frequency and the PRACH 5, 6 of the main carrier frequency.

When the UE selects the association combination 1 and the association combination 2, the method for accessing the multi-carrier frequency system is completely the same as that in the prior art. When the UE selects the association combination 3, the UE selects the SYNC-UL code (0, 1, 2, 3) of the secondary frequency point 1, UTRAN can only feedback through the FPACH2 of the main frequency point, and the UE can only send it through the main frequency point PRACH3 Access messages.

When the UE selects the association combination 5, the UE selects the SYNC-UL code (0, 1, 2, 3) of the secondary frequency point 2, and the UTRAN can only perform feedback through the FPACH4 of the primary frequency point. Which PRACH channel to use can be determined according to the feedback time. When the FPACH feedback time is the subsequent even-numbered subframe (2, 4, 6) of the SYNC-UL transmission subframe, the UE will use the main frequency point PRACH6 to send the access message. When the FPACH feedback time is the subsequent odd-numbered subframe (1, 3, 5) of the SYNC-UL transmission subframe, the UE will use the main frequency point PRACH5 to send the access message.

The interrelated Fast Physical Access Channel (FPACH) and Random Access Physical Channel (Physical Random Access Channel, PRACH) are still limited to the main carrier frequency. The UE can access on the uplink pilot channel (Uplink Pilot Channel, UpPCH) of the main carrier frequency, and can also access on the uplink pilot channel (Uplink Pilot Channel, UpPCH) of the auxiliary carrier frequency. However, since the frequency points of the main carrier frequency and the auxiliary carrier frequency equipped with the UpPCH are different, using the same uplink synchronization code (Synchronization-Uplink, SYNC-UL) will not cause interference.

The specific implementation steps of the multi-carrier frequency system access solution will be described in detail below with reference to FIG. 7 .

First, step S101 is executed, that is, the network configures primary and secondary carrier frequency access channel resources and their associations. In the process of loading configuration, the configuration is divided into the following parts:

1. The network configures common channels on the main carrier frequency: Downlink PilotCHannel (DwPCH), Uplink Pilot Channel (UpPCH), Primary Common Control Physical Channel (PCCPCH), Secondary Common Control Physical Channel (SCCPCH), Paging Indicator Channel (Paging Indicator Channel, PICH), Random Access Physical Channel (Physical Random Access Channel, PRACH) and Fast Physical Access Channel (FastPhysical Access Channel) , FPACH), this step is the same as the prior art solution.

2. The network configures an Uplink Pilot Channel (Uplink Pilot Channel, UpPCH) channel on the auxiliary carrier frequency, and its uplink synchronization code (Synchronizatton-Uplink, SYNC-UL) code set can be the same as the default condition of the main carrier frequency, or it can be different . When the uplink synchronization code (Synchronization-Uplink, SYNC-UL) code set of the secondary carrier frequency uplink pilot channel (Uplink Pilot Channel, UpPCH) is different from that of the main carrier frequency uplink pilot channel (Uplink Pilot Channel, UpPCH), it is necessary to The uplink synchronization code (Synchronization-Uplink, SYNC-UL) code set of the auxiliary carrier frequency is broadcast in the system information of the main carrier frequency.

3. The network configures more Fast Physical Access Channel (FPACH) and Random Access Physical Channel (Physical Random Access Channel, PRACH) on the main carrier frequency to cooperate with the newly added uplink pilot on the auxiliary carrier frequency channel (Uplink PilotChannel, UpPCH); and broadcast these newly added fast physical access channel (Fast Physical Access Channel, FPACH) / random access physical channel (PhysicalRandom Access Channel, PRACH) and the secondary carrier frequency system information The corresponding relationship of the uplink pilot channel on the carrier frequency.

Then, the next step S102 is executed, that is, the network counts the access resources on all main carrier frequencies and auxiliary carrier frequencies in the cell, assigns these resources to different access service classes (Access ServiceClass, ASC), and broadcast in frequent system information.

Then, there is the UE random access part. The UE random access includes three processes: random access preparation, random access, and random access conflict handling. The UE first enters the random access preparation state, that is, the UE executes step S103, reads the above cell broadcast information, and obtains access resource configuration and associated information therefrom. It is carried out in the following parts:

When the UE is in idle mode, it will maintain downlink synchronization and read the above cell broadcast information. From the downlink pilot time slot (Downlink Pilot Time Slot, DwPTS) used by the main carrier frequency of the cell, 32 downlink synchronization codes (Synchronization-Downlink, SYNC-DL) are transmitted, and each SYNC-DL has a unique serial number 0, 1, 2...31, on the DwPTS, the UE can obtain random access and allocate 8 uplink synchronization codes ( Synchronization-Uplink, SYNC-UL) (characteristic signal) code set. The code set has a total of 256 different uplink synchronization code (Synchronization-Uplink, SYNC-UL) sequences, and the sequence number is divided by 8, and the downlink synchronization code (Synchronization-Uplink) in the downlink pilot time slot (Downlink PilotTime Slot, DwPTS) can be obtained. -Downlink, SYNC-DL) serial number. When it is not divisible by 8, it is rounded up, assuming that the sequence number of SYNC-DL is X, and the number of SYNC-UL is d, then u/8=d. There are 8 u that satisfy this formula, 8d, 8d+1, 8d+2, ..., 8d+7. From the system information of the primary frequency broadcast cell, the UE reads the primary frequency broadcast channel, and the UE obtains which uplink synchronization codes (Synchronization-Uplink, SYNC-UL) in the primary carrier frequency code set can be used, and also obtains the related information Detailed information (code, spreading factor, midamble code and time slot) of random access physical channel (Physical Random Access Channel, PRACH) and fast access physical channel (Fast Physical Access Channel, FPACH) and others related to random access relevant information.

In addition, the UE obtains which secondary carrier frequencies are configured with the Uplink Pilot Channel (Uplink Pilot Channel, UpPCH), as well as the uplink synchronization code (Synchronization-Uplink, SYNC-UL) code set used by it, and the codes that can be used. Detailed information of the random access physical channel (PhysicalRandom Access Channel, PRACH) and fast access physical channel (Fast PhysicalAccess Channel, FPACH) (used code, spreading factor, midamble code and time slot) and others related to random access relevant information. The UE obtains the PRACH and the Fast Physical Access Channel (FPACH) related to the uplink pilot channel (Uplink Pilot Channel, UpPCH) of the auxiliary carrier frequency and configures them on the main carrier frequency.

The information contained in the BCH also includes different carrier frequency uplink synchronization codes (Synchronization-Uplink, SYNC-UL) and fast access physical channel (Fast Physical Access Channel, FPACH) resources, fast physical access channel (Fast Physical Access Channel) , FPACH) and PRACH resources are interrelated. As shown in Figure 6, the eight SYNC-UL codes on the main carrier frequency, auxiliary carrier frequency 1 and auxiliary carrier frequency 2 are 0, 1, 2, 3, 4, 5, 6, 7 respectively; 5 EPACHs, respectively FPACH0, FPACH1, FPACH2, FPACH3, FPACH4; 7 PRACHs, PRACH0, PRACH1, PRACH3, PRACH4, PRACH5, PRACH6. They can be divided into 5 association combinations, association combination 1, that is, SYNC-UL 0, 1, 2, 3 located in the main carrier frequency corresponds to FPACH 0 of the main carrier frequency and PRACH 0, 1 of the main carrier frequency; association combination 2, That is, SYNC-UL 4, 5, 6, and 7 located on the main carrier frequency correspond to FPACH1 on the main carrier frequency and PRACH2 on the main carrier frequency; association combination 3, that is, SYNC-UL 0, 1, 2 on the auxiliary carrier frequency 1, 3 corresponds to the FPACH 2 of the main carrier frequency and the PRACH3 of the main carrier frequency; the association combination 4, that is, the SYNC-UL 4, 5, 6, 7 located in the auxiliary carrier frequency 1 corresponds to the FPACH3 of the main carrier frequency and the PRACH 4 of the main carrier frequency ; Association combination 5, that is, SYNC-UL 0, 1, 2, 3 located at auxiliary carrier frequency 2 corresponds to FPACH 4 of main carrier frequency and PRACH 5, 6 of main carrier frequency.

Therefore, when the UE sends an uplink synchronization code (Synchronization-Uplink, SYNC-UL) sequence, according to the above association relationship, it can obtain which Fast Physical Access Channel (FPACH) resources and Random access physical channel (Physical Random Access Channel, PRACH) resource. For example, if the UE selects the association combination 1 and the association combination 2, the method for accessing the multi-carrier frequency system is completely the same as that in the background technology. When the UE selects the association combination 3, the UE selects the SYNC-UL code (0, 1, 2, 3) of the secondary frequency point 1, UTRAN can only feedback through the FPACH2 of the main frequency point, and the UE can only send it through the main frequency point PRACH3 Access message; if the UE selects the association combination 5, the UE selects the SYNC-UL code (0, 1, 2, 3) of the secondary frequency point 2, and the UTRAN can only feed back through the FPACH4 of the primary frequency point. Which PRACH channel to use can be determined according to the feedback time. When the FPACH feedback time is the subsequent even-numbered subframe (2, 4, 6) of the SYNC-UL transmission subframe, the UE will use the main frequency point PRACH6 to send the access message. When the FPACH feedback time is the subsequent odd-numbered subframe (1, 3, 5) of the SYNC-UL transmission subframe, the UE will use the main frequency point PRACH5 to send the access message.

The UE then performs a random access procedure. The UE's random access process is divided into the following parts.

First, step S104 is executed, that is, the UE determines the available uplink synchronization code (Synchronization-Uplink, SYNC-UL) code set according to its own ASC and system information, that is, which carrier frequency (primary carrier frequency or auxiliary carrier frequency) can be used ) on which codes. The ASC corresponds to the priority of the UE. Generally, a UE with a high priority can use more random access resources, and the probability of collision during access is small. However, users with low priority can use less access resources, and the probability of conflict during access is high. Different ASCs correspond to different association combinations in the above association table, and the UE can select the SYNC-UL in this combination. Some ASCs can correspond to multiple combinations, or even all combinations. Obviously, at this time, the UE can select a wide range of SYNC-UL.

Next, step S105 is executed, that is, the UE randomly selects one of 8 possible uplink synchronization codes (Synchronization-Uplink, SYNC-UL), and then according to the UpPTS time calculated from the DwPTS time, the power determined by the open-loop power control, and the measured The obtained path loss and the received power of the UpPTS target broadcast by the system, the UE can determine the transmission time and power of the Uplink Pilot Channel (Uplink Pilot Channel, UpPCH) according to the received power, and then select the uplink synchronization code to pass the uplink pilot channel (Uplink Pilot Channel, UpPCH) sent to the base station. Next is step S106, that is, the UE monitors on the Fast Physical Access Channel (FPACH) on the main carrier frequency corresponding to the uplink synchronization code (Synchronization-Uplink, SYNC-UL) to receive the FPACH at any time .

Then execute step S107, that is, after receiving the uplink synchronization code (Synchronization-Uplink, SYNC-UL) sent by the UE, the base station NodeB in the network searches for the corresponding FPACH according to the received SYNC-UL to determine the transmission power and timing Adjustment. That is, if the time is ahead, the amount of time delay is given, otherwise, the amount of time advance is given; if the power is too high, the amount of power reduction is given, otherwise, the amount of power increase is given. Subsequently, the power and time adjustment are sent to the UE through a Fast Physical Access Channel (FPACH) within the next 4 subframes.

Next, step S108 is executed. After the UTRAN sends the time adjustment and power adjustment information to the UE, it changes to monitor the corresponding PRACH state to prepare for receiving access information.

Then step S109 is executed, the UE receives the above control information from the related Fast Physical Access Channel (FPACH) on the main carrier frequency. Because FPACH/PRACH is only configured on the main carrier frequency, after the UE sends UpPTS on the auxiliary carrier frequency, then the access action is transferred to the main carrier frequency, and the associated Fast Physical Channel (Fast Physical Channel) on the main carrier frequency Access Channel, FPACH) to receive the above control information,

Then step S110 is executed, that is, the UE adjusts the transmission power and time, and ensures that after the next two frames, the random access physical channel corresponding to the Fast Physical Access Channel (FPACH) at the main carrier frequency (Physical Random AccessChannel, PRACH) to send access messages.

Once the UE receives the above control information from the Fast Physical Access Channel (FPACH), in order to send it to the UTRAN with the most appropriate power at the correct time, the UE will send it according to the control information sent by the UTRAN. Adjust the transmission power and time, such as delay or advance the transmission time, increase or decrease the power, to ensure that in the next two frames, the random access physical channel corresponding to the Fast Physical Access Channel (FPACH) Channel (Physical Random Access Channel, PRACH) to send access messages.

Finally, step S111 is executed, that is, when the UTRAN monitors that there is access information on the corresponding PRACH, the access information is received.

It can be seen from the above that the random access of the UE on the main carrier frequency is the same as the existing solution. When initiating random access on the auxiliary carrier frequency, it is necessary to send SYNC-UL on the uplink pilot channel (Uplink PilotChannel, UpPCH) of the auxiliary carrier frequency, and then transfer to the main carrier frequency for receiving FPACH and sending PRACH.

3. Random access conflict handling

In the case of a possible collision, or in a poor propagation environment, the UE does not get any response from the Node B. Therefore, the UE must adjust the transmission time and transmission power through new measurements, and after a random delay, transmit a re-randomly selected uplink pilot channel (Uplink Pilot Channel, UpPCH) on the main carrier frequency or auxiliary carrier frequency. Uplink synchronization code (Synchronization-Uplink, SYNC-UL).

The above is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto, any changes or variations that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention Replacement should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be determined by the protection scope of the claims.

Claims (7)

1. A method for accessing a multi-carrier frequency system, applied to a multi-carrier frequency system including user equipment, characterized in that it includes: A. The system determines the relationship between the fast access physical channel and the random access physical channel on the main carrier frequency and the pre-configured uplink pilot channel on the auxiliary carrier frequency; B. Configuring a quick access physical channel and a random access physical channel on the main carrier frequency according to the association relationship; C. The user equipment obtains access resource configuration and associated information according to the main carrier frequency broadcast; the user equipment sends the uplink synchronization code on the uplink pilot channel of the auxiliary carrier frequency; D. Receive information fed back by the system through the fast access physical channel on the main carrier frequency, and send an access message on the corresponding random access physical channel of the main carrier frequency according to the feedback information, and complete system access. 2. The method for multi-carrier frequency system access according to claim 1, characterized in that, between C and D also includes: The system judges whether the uplink synchronization code of the auxiliary carrier frequency is the same as the uplink synchronization code of the main carrier frequency. If they are the same, then execute step D. If not, the system broadcasts the uplink synchronization code of the auxiliary carrier frequency on the main carrier frequency to the user terminal . 3. The method for multi-carrier frequency system access according to claim 2, wherein said step D further comprises: Judging whether the fast access physical channel on the main carrier frequency has received feedback information, and if so, sending an access message on the corresponding random access physical channel of the main carrier frequency; otherwise, wait for a period of time and return to step D. 4. The method for multi-carrier frequency system access according to claim 3, further comprising: An association relationship table is established in the system to store the association relationship between the fast access physical channel and the random access physical channel on the main carrier frequency and the uplink pilot channel on the auxiliary carrier frequency. 5. The method for accessing a multi-carrier frequency system according to claim 4, further comprising: before returning to step D, the user equipment readjusts the transmission time and transmission power. 6 . The method for multi-carrier frequency system access according to claim 5 , further comprising: before the sending of the access message, the user equipment adjusts the transmission time and transmission power. 7. The method for accessing a multi-carrier frequency system according to claim 6, characterized in that 8 or less than 8 uplink synchronization codes are configured on the uplink pilot channel on the secondary carrier frequency.

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