CN1194565A - Base station selecting method, reference signal receiving method and user equipment - Google Patents

Abstract

A base station selecting method, a reference signal receiving method, and a subscriber apparatus by which base stations to be monitored can be efficiently selected with a simple structure, wherein a pilot signal detector includes a counter member for counting prescribed time information; a selecting member for selecting a base station for detecting a pilot signal for each frame forming a spectrum diffusion signal based on the value of the time information; and a detecting member for detecting the timing of the pilot signal transmitted from the base station selected by the selecting member. The base stations are selected for each frame based on the prescribed time information and the timings of the selected base stations are detected. Therefore, the number of the base stations to be monitored during a detection of a timing for one can be minimized as required and a consumed electric power corresponding to the number of times of the detection of timings can be lowered.

Description

Base station selecting method, reference signal receiving method and subscriber equipment

The present invention relates to base station selecting method, reference signal receiving method and subscriber equipment and particularly can be applicable to pilot signal detector, pilot signal detection method and be used in the mobile communication terminal device that communicates by for example code division multiple access (CDMA) method in the mobile communication system.

Routinely, shared when communicating by many users, utilized the technical method such as frequency division pattern, time division multiplexing, code division multiple access pattern, so that avoid the interference between corresponding each telex network circuit when a base station.These methods have merits and demerits respectively and depend on that the purpose of communication system correspondingly selects.

For example, according to code division multiple access (CDMA (code division multiple access) hereinafter referred to as) method, the sign indicating number (PN sign indicating number (PN (pseudo noise) sequence) hereinafter referred to as) of the regulation of respective lines is distributed in use, a frequency range (hereinafter this is called as spread spectrum) that makes the modulated wave of same carrier frequencies be extended to be wider than original frequency range and be re-used and the modulated wave through multiplexing that obtains is carried out transmission through the corresponding modulated wave of spread processing.In addition, the spread-spectrum signal that is received respectively with by will be synchronous by the PN sign indicating number that the circuit of demodulation is presented.Therefore, only identify needed circuit.

Specifically, beginning, sender side initially distributes different PN sign indicating numbers to give corresponding each circuit.In this case, the PN sign indicating number is made up of a series of pseudo random number sign indicating numbers.Sender side utilizes different PN sign indicating numbers to multiply by the modulated wave that sends by each respective lines respectively and obtains modulated wave through spread processing.In this respect, corresponding modulated wave elder generation's modulation treatment before they stand spread processing through being scheduled to.By this way, carry out multiplexing and obtain multiplexing modulated wave sending through the modulated wave of spread processing respectively.

Then, at receiver side, the received signal that sends from sender side respectively with distribute to this circuit and will be undertaken synchronously by the identical PN sign indicating number of demodulation and multiply each other.Therefore, the modulated wave that only sends by target line is by demodulation.

By this way, according to CDMA pattern or method, only when identical PN sign indicating number was given sender side and receiver side by common setting, communication can directly be carried out between each is called out.In addition, according to CDMA pattern or method, because use different PN sign indicating numbers respectively for corresponding each circuit, so that modulated wave stands spread processing, thereby only can demodulation send by circuit will be by the spread-spectrum signal of demodulation for receiver side.Have again,, we can say that the CDMA pattern is desirable on maintaining secrecy because the PN sign indicating number comprises a series of pseudorandom numbers.

In addition, according to the mobile communication system of utilizing CDMA pattern or method, PN sign indicating number (pilot signal hereinafter referred to as) is repeated to send in the base station of sender side, so that acquisition and maintenance user side and regeneration time clock is synchronous.The user of receiver side detects the corresponding pilot signal that sends from a plurality of base stations and distributes each demodulator of timing that is detected respectively.In this case, the user produces the PN sign indicating number in corresponding each demodulator.Each demodulator utilizes in the timing of distributing to each demodulator the spread-spectrum signal that sends from target BS to multiply by the PN sign indicating number respectively, therefore demodulation spread spectrum signal correctly.

Specifically, according to the mobile communication system of utilizing CDMA pattern or method, each base station utilizes corresponding different timing to send the PN sign indicating number as pilot signal accordingly.User side detects the timing of the pilot signal of presenting from target BS and the PN sign indicating number that utilizes this timing to produce synchronously in demodulator, make the user only demodulation correctly from the spread-spectrum signal of target BS transmission.

Say that by the way as mentioned above, relevant base station is at each different timed sending PN sign indicating number, still, each PN code book body is to form respectively with identical sign indicating number type.In other words, for each base station in the difference on regularly between the different pilot signal directly corresponding to the difference between each PN sign indicating number.

Meanwhile, above-mentioned user carries out a kind of mobile communication, makes it move, simultaneously as with the Target Transformation base station of this telex network.A kind of like this conversion of base station is called switching.In order to realize effective switching, the user is designed to constantly monitor the timing of the pilot signal of each base station (neighbor base station hereinafter referred to as) except the target BS that communicates with current this user.

Change method according to the CDMA pattern, each neighbor base station is by the timing by the detection pilot signal, and promptly phase place is monitored.Therefore, priority according to the rules is divided into some groups with each monitored base station, so that monitor for these base stations that are applied to a suitable system.

But, exist inconvenience like this, that is, be used for selecting concrete standard can not be stipulated in CDMA pattern or method with monitored base station.Therefore, need obtain a kind of simple effective method and equipment that is used to select monitored base stations, so that reduce the power consumption of user side.

In view of the foregoing, the purpose of this invention is to provide a kind of base station selecting method, a kind of reference signal receiving method and a kind of subscriber equipment,, utilize simple structure just can select effectively monitored base station by this method and apparatus.

Carry out demodulation by receiving for the setting of the base station selecting method of cellular system, in the user from the reference signal of base station with based on this reference signal, above-mentioned purpose of the present invention and other purpose have been implemented.Base station selecting method comprises: the timing information that is used for picking up from the reference signal that receives timing information picks up step; Be used for from select the selection step of a predetermined base station corresponding to each base station of this timing information; With the reference signal receiving step that is used for receiving reference signal from this predetermined base station.

In addition, according to the present invention, receiving reference signal and carry out based on this reference signal among the user of demodulation from each base station, the method for reseptance that is used for the reference signal of cellular system comprises: the timing information that picks up timing information from the reference signal that receives picks up step; Be used for selecting a plurality of selection steps regularly that receive of out of phase from timing information; With the reference signal receiving step that in a plurality of each timing that receives regularly, receives reference signal.

In addition, according to the present invention, the subscriber equipment in cellular system is from base station selected reference signal with based on base station of this reference signal selection, and this equipment comprises: the receiving system that is used for received RF signal; Be used for picking up the timing information pick device of timing information from the output signal of receiving system; Be used for selecting the base station selection apparatus of a predetermined base station from each base station of the output signal of the timing information pick device of one of a plurality of timing informations of receiving corresponding to out of phase; Be used for from the demodulation reference signal device of a predetermined base station demodulated reference signal.

After having read following detailed in conjunction with the accompanying drawings, characteristic of the present invention, principle and use become apparent, and same parts is by identical label or character representation in each accompanying drawing.

In each accompanying drawing:

Fig. 1 is the formation of expression according to the subscriber equipment of one embodiment of the present of invention;

Fig. 2 is the schematic diagram of explanation system's definition status under wait state; With

Fig. 3 is explanation detects the method for pilot signal according to embodiments of the invention a flow chart.

With reference to each accompanying drawing the preferred embodiments of the present invention are described.

With reference to Fig. 1, usually, subscriber equipment of label 1 expression, this equipment is as receiving from utilizing CDMA (code division multiple access: the signal of a plurality of base stations transmission of pattern or method code division multiplexing).Corresponding each base station transmission is multiplied each other with corresponding different timing by the sign indicating number with each PN sign indicating number (pseudo noise series) together and the PN sign indicating number that is multiplied each other is applied the data that the spread processing (not shown) produces.

Subscriber equipment 1 receives the transmission data that send from corresponding each base station and is included in the signal that the timing demodulation of the pilot signal the received signal is received by utilization.Therefore, subscriber equipment 1 received signal of demodulation only from being received by the base station of demodulation.In this respect, pilot signal comprise the PN sign indicating number with corresponding different timing duplication code type signal these regularly send by each base station of transmitter side and be used to obtain and keep user side synchronously and regeneration time clock.

Subscriber equipment 1 is baseband signal S2 by the received signal S1 that antenna multicoupler 3, high-frequency amplifier 4 and 5 conversion of quadrature detection circuit are received by antenna 2 sequentially.The baseband signal S2 that obtains is fed to receiver 6 by A/D conversion (not shown) and the signal that therefore obtains.The baseband signal S2 that receiver 6 is presented as input is to as the demodulator 7,8,9 of demodulating equipment with to the receiving system as the timing detector 10 of pilot signal detection device.Timing detector 10 detects the pilot signal that is sent by each base station from baseband signal S2.In addition, timing detector 10 distributes each regularly to give demodulator 7,8,9 respectively based on each pilot signal that detects. Demodulator 7,8,9 respectively in the timing of distributing to it demodulated base band signal S2 and the demodulated signal S3 that transmit to obtain respectively, S4, S5 to integration unit 11.

More particularly, demodulator 7,8,9 produces the PN sign indicating number respectively and utilizes baseband signal S2 to multiply by this PN sign indicating number in above-mentioned each timing, makes baseband signal S2 by demodulation.The timing that sends each PN sign indicating number in the distinctive timing is being distinguished in corresponding each base station to each base station.Therefore, by pilot signal presented each regularly be with those PN sign indicating number synchronised with utilize this synchronous PN sign indicating number demodulated base band signal S2, only make from the selectively demodulation of signal that will be sent by the base station of demodulation.In this case, the aforesaid timing that is illustrated in the pilot signal is referred to as locking with the processing that produces the timing synchronised of PN sign indicating number in each demodulator.

Here, demodulator 7,8,9 uses and has the baseband signal S2 that the demodulation of corresponding different timing PN sign indicating number is presented.That is to say, be not only by having the signal that transmission channel received of constant propagation path length from each signal that each base station sends, and for example also have by the reflection of the barrier such as various buildings, and by receiver by having the signal that corresponding different spread length receives.Be called as multipath at a plurality of reflected waves that receive in such a way by a plurality of transmission channels.In fact, because multipath is to exist usually, receiver 6 is configured to demodulator 7,8,9 and depends on the number of multipath and can start them from its number that receives the base station of signal.In this case, the signal S1 that receives by the transmission channel that comprises three paths (that is only regularly being under the different state) is carried out demodulation by demodulator 7,8,9 respectively.

Integration unit 11 inputs and demodulated signal S3, the S4 and the S5 that comprehensively obtain from above-mentioned multipath.At this moment because demodulated signal S3, S4 and S5 respectively on different timing by demodulation, integration unit 11 timing of demodulated signal S3, S4 and S5 synchronously reciprocally and then comprehensively by the signal of demodulation.Integration unit 11 mutually comprehensive demodulated signal S3, S4 and S5 make the reception data S6 that it can produce big noise ratio and the reception data S6 and the output of interference ratio is obtained.

In this respect, subscriber equipment 1 also provides a circuit that is used for transmitting system, and this circuit works to present transmission data S7 and applies Quadrature Phase Shift Keying (QPSK) to modulating part 12 with to these data, after this these data is applied spread spectrum.Subscriber equipment 1 sequentially amplifies modulated signal S8 that produces like this and the modulated signal that is exaggerated by antenna multicoupler 3 and antenna 2 transmissions in the modulating part 12 of high-frequency amplifier 13.

Have, the control section 14 that plays the counting device effect is connected to timing detector 10 again.Control section 14 is designed to produce as the timing information S9 of count value and presents timing information to timing detector 10.Timing detector 10 monitors the timing at each neighbor base station or similar station and judges the timing that is newly assigned to demodulator 7,8,9 between transfer period based on timing information S9.

Control section 14 for example using system regularly as timing information S9.This system's timing indicator be shown in the U.S. normalized IS-95 system fiducial time information and the absolute time on January 6th, 1980 be considered to a benchmark.In the IS-95 system, the base station was designed to be by the control channel transmitting system time.

Subscriber equipment 1 plays a user's effect, when energized, detects the timing (PN sign indicating number) of desired base station and begin to upgrade the count value of control section 14 in this timing.After this, subscriber equipment 1 connects the control channel of described base station, the count value of value initialization's control section 14 that detection system timing and utilization are obtained.Subscriber equipment 1 is count initialized value and after subscriber equipment is transferred to wait state by this way, utilizes the count value of control section 14 to keep and the update system time.In the IS-95 system, during wait state, system time is used to definite intermediary operation timing, judges that the message in control channel sends the time of timing and appointment switching etc.

Get the count value of 36 bits as a unit from the system time representative that base station side sends, this is worth every 80ms and is updated once.In this case, because can be used as the value of a unit according to the value of in IS-95, calling out control criterion 20ms, user side expands and increases the least significant bit of two bits in this value, make and to get 38 bits that this is worth every 20ms and is updated once and the system time that obtains the 20ms unit as a unit.

Fig. 2 is illustrated in during the wait state in bring drill to an end system time condition in doing of indirect.Be illustrated in 4 times of the frame reception of the reception among Fig. 2 based on the 20ms unit.Continue calling be assigned to each received frame of other user.For example, when hypothesis in the figure intercycle is 1.23S, the 80ms that 16 users are repeatedly distributed to this cycle and this cycle gives any user to receive regularly.

Shown in this drawing, a timing is represented in a unit of received frame, and this timing is consistent with the renewal of the system time with 20ms unit that obtains by two bits that upgrade above-mentioned least significant bit.IS-95 system regulation: value of system time indication, this value are at above-mentioned intermediary operation regularly the time, are removed by 4 to obtain when receiving beginning.Therefore " Tn " that is illustrated among Fig. 2 represents 4 multiple.Apparent from top description, when the supposing the system time be 4 residue number system constitute the time, regularly can be divided into and comprise 0,1,2 and 3 four type in bring drill to an end reception during doing of indirect.

Subscriber equipment 1 is designed to be the timing that utilizes each neighbor base station of said system time monitoring.

Carry out predetermined timing according to following process and monitor processing.That is, as shown in Figure 3, subscriber equipment 1 begins to start this process at step SP1.Detect from the subscriber equipment 1 of the received frame of base station side at waiting time and to carry out corresponding to the processing of this received frame and obtain system time at step SP2 then.More particularly, timing detector 10 is read the count value that is produced system time by control section 14.

Next, two least significant bits of the system time that subscriber equipment 1 calculates are so that calculate 4 residue number system at step SP3.Subscriber equipment 1 is determined the base station that is monitored based on the remainder that calculates by this way.

Wherein, detected base station can be classified as three groups during wait state.That is, these three groups comprise: the A group with the current base station from its receipt of call of subscriber equipment; Be used as the B group that the neighbor base station of the current base station that is receiving monitors; With the C group that is not above-mentioned each base station.Subscriber equipment 1 thinks that order A, B and C are used to monitor each base station, a kind of priority.When the remainder that obtains at step SP3 was 0 and 1, this processing advanced to step SP4.When remainder was 2, this processing advanced to step SP6.When remainder was 3, this processing was carried out branch respectively and is advanced to step SP8.

When the remainder that obtains at step SP3 was 0 and 1, subscriber equipment 1 selected the A group as in base station that step SP4 will be monitored.Then, subscriber equipment 1 is selected a base station and is detected its timing (supervision) at step SP5 from A group.

Also have, when the remainder that obtains at step SP3 is 2, subscriber equipment 1 select the B group as at step SP6 with the base station that is monitored.Then, subscriber equipment 1 detects its timing (supervision) from base station of B group selection with at step SP7.

Also have again, when the remainder that obtains at step SP3 is 3, subscriber equipment 1 select the C group as at step SP8 with the base station that is monitored.Then, subscriber equipment 1 detects its timing (supervision) from base station of C group selection with at step SP9.

At step SP5, SP7 and SP9 in any case, when the timing of finishing selected base station detects, finish this at step SP10 and cross program.After this, when received frame was detected, processing was returned to step SP2 and repeats this process.Subscriber equipment 1 is designed to store its regularly Be Controlled part 14 base station that each group is detected, with next time regularly between detection period (step SP5, SP7 and SP9) detect the timing of each different base stations by consulting this memory.Under the situation of A group, because it comprises the base station of a calling of the current reception of this subscriber equipment, so the base station that only exists a quilt to deposit.Therefore, only in this case, the timing of each same base is detected, is changed until this base station of subscriber equipment receipt of call.

Utilize above-mentioned formation, subscriber equipment 1 utilizes control section 14 generations, maintenance and update system time S9.

System time S9 representative utilizes count value forming with reference time information synchronised that is sent by the base station and consistent value and is updated in the corresponding to timing of transmission timing of each frame that sends to subscriber equipment 1 from the base station.

Subscriber equipment 1 depends on priority to divide each base station that will be monitored is A, B and three groups of C and each component is fitted on by the value of system time S9 removed each remainder that obtains by 4.Subscriber equipment 1 calculates 4 residue number system for the value of the dibit least significant bit of said system time S9, this system time be each frame of receiving from the base station each regularly be the time of every 20ms.Then, subscriber equipment 1 depends on the value that is obtained, and selects one of corresponding group A, B and C, detect selected group a base station timing and detect after forward low-power consumption mode to.

As mentioned above, system regularly is important information in the communication.Subscriber equipment 1 accurately produces system regularly usually.Subscriber equipment 1 forwards low-power consumption mode to after regularly selecting the base station that will be monitored and subscriber equipment 1 to detect the timing of selected base station according to system.Therefore, the simple structure of subscriber equipment utilization can easily be selected the base station that will be monitored and reduce power consumption.

According to above-mentioned formation, because produce the system time S9 of reference time information by control section 14, select the base station that is monitored according to system time S9 during wait state for each received frame, after detecting the timing of selected base station at subscriber equipment, subscriber equipment is transferred to low-power consumption mode, until next received frame, under the situation that extra additional structure is not provided, can easily select the base station that to be monitored.Therefore, can select the subscriber equipment with simple structure 1 of the base station that will be monitored to be implemented effectively.

Though, receiver 6 and subscriber equipment 1 with three demodulators 7,8 and 9 have been described in the above-described embodiments, be to be understood that the present invention is not limited only to such form, and can be applied to and have, for example the receiver of five demodulators and subscriber equipment.In other words, utilize each demodulator of the signal that can a plurality of demodulator demodulation receives according to CDMA pattern or method, and need not consider their number from each base station.

In addition, be applied to example in the subscriber equipment 1 with receiving function and sending function though described the present invention in the above-described embodiments, but it should be noted that the present invention is not limited to this example, and can be applied to the subscriber equipment 1 that receiving function is only arranged.

Also have again, though describing in the above-described embodiments during wait state, promptly bring drill to an end and select the subscriber equipment 1 of the base station that will be monitored during doing in indirect, but will be appreciated that the present invention is not limited to this, and can be applied at continuous reception period, for example during conversing, select the subscriber equipment of the base station that will be monitored.In this case, because can judging, user side will be added to from it at present just in the A of receipt of call group by a group of demodulation, deposit in the B group and the group of the C except that them for neighbor base station, the corresponding base station of respectively organizing is determined and adopts residue number system to determine regularly so that select the method for corresponding each group to be changed, and makes above-mentioned example to satisfy to be used for the method for selecting the base station that will be monitored according to embodiments of the invention.

In addition, judge as each base station that will be monitored, comprise when the dibit least significant bit by system time is removed the remainder that obtains and is 0 or 1 by 4 from its user and just organizing at present at the A of the base station of receipt of call though described subscriber equipment in the above-described embodiments; Comprise the B group of when remainder is 2, being deposited each base station as neighbor base station; With the C group that comprises the base station except A group or B group when remainder is 3; Should be noted in the discussion above that the present invention is not limited to this.The present invention can be applied to, and for example subscriber equipment is judged as each base station that will be monitored: comprise when being 0 by the remainder that is obtained by the 4 dibit least significant bits that remove system time from its user and just organizing at the A of the base station of receipt of call at present; Comprise the B group of when remainder is 1 or 2, being deposited each base station as neighbor base station; With the C group that comprises the base station except A group or B group when remainder is 3.

Also have, though described control section 14 in the above-described embodiments, this part maintenance and renewal are as a unit of system time, and all 38 bits as a count value should be noted that the present invention is not limited to this.And for example, only some of least significant bit can may be stored according to software by actual count and remaining highest significant position.

As mentioned above, according to the invention provides: the counting device that is used to count stipulated time information; Be used for detecting the choice device of the pilot signal base station of each frame that forms the spread-spectrum signal selection according to the temporal information value; With the timing detection device that is used to detect from the pilot signal that sends by the selected base station of choice device; Every frame of feasible temporal information is according to the rules selected the timing of the selected base station of base station and detection.Therefore, between the timing detection period, the number of base stations that is monitored can be minimized as requested.Therefore, can realize pilot signal detector, pilot signal detection method and can select the mobile communication terminal device of the base station that is monitored effectively with simple structure by it.

Though be described in conjunction with the preferred embodiments of the present invention, but for the professional and technical personnel, can make various changes and modification, therefore, in the time of in falling into true spirit of the present invention and scope, appending claims covers all such change and modifications.

Claims (13)

1. receiving the base station selecting method that is used for cellular system reference signal and the subscriber equipment from the base station, comprising based on described demodulation reference signal:

The timing information that is used for picking up from the reference signal that receives timing information picks up step;

Be used for from select the selection step of a predetermined landing corresponding to described each base station of described timing information; With

Be used for receiving the reference signal receiving step of reference signal from a described predetermined base station.

2. receiving the reference signal receiving method that is used for cellular system reference signal and the subscriber equipment from the base station, comprising based on described demodulation reference signal:

The timing information that is used for picking up from the reference signal that receives timing information picks up step;

Be used for selecting the reception selection step regularly of a plurality of outs of phase from described timing information; With

Be used in described a plurality of each timing that receives regularly, receiving the reference signal receiving step of reference signal.

3. according to the base station selecting method of claim 1, wherein said cellular system uses the CDMA form.

4. according to the reference signal receiving method of claim 2, wherein;

Described cellular system uses the CDMA form.

5. according to the reference signal receiving method of claim 2, wherein;

Described reference signal receiving step is carried out by a plurality of demodulators.

6. according to the base station selecting method of claim 1, wherein;

Described selection step is carried out according to the interval receiving mode.

7. according to the base station selecting method of claim 3, wherein;

The reference time length that is used to pick up in the step picking up of described timing information is 4 time limits of scheduled unit time.

8. according to the reference signal receiving method of claim 4, wherein;

Pick up 4 time limits that the reference time length that is used to pick up in the step is the scheduled unit time at described timing information.

9 subscriber equipment, these subscriber equipmenies in cellular system receive reference signal and based on base station of described reference signal selection, comprising from each base station:

The receiving system that is used for received RF signal;

Be used for picking up the timing information pick device of timing information from the output signal of described receiving system;

Be used for from select the base station selection apparatus of a predetermined base station corresponding to described each base station of the described timing information pick device output signal of one of a plurality of out of phase timing informations that receive; With

Be used for the demodulation reference signal device of demodulation from the reference signal of a described predetermined base station.

10. according to the subscriber equipment of claim 9, wherein;

Described cellular system uses the CDMA form.

11. according to the subscriber equipment of claim 9, wherein;

Described demodulation reference signal device has a plurality of.

12. according to the subscriber equipment of claim 9, wherein;

Described selection operation is carried out according to the interval receiving mode.

13. according to the subscriber equipment of claim 10, wherein;

The reference time length that is used to pick up in described timing information pick device is 4 time limits of scheduled unit time.

Images