CN206620115U

CN206620115U - Mobile terminal and its control circuit for improving TDD segment sensitive degree

Info

Publication number: CN206620115U
Application number: CN201720117210.8U
Authority: CN
Inventors: 王文
Original assignee: Huizhou TCL Mobile Communication Co Ltd
Current assignee: Huizhou TCL Mobile Communication Co Ltd
Priority date: 2017-02-08
Filing date: 2017-02-08
Publication date: 2017-11-07
Anticipated expiration: 2027-02-08

Abstract

The utility model discloses mobile terminal and its for improving the control circuit of TDD segment sensitive degree.Wherein, control circuit includes：Antenna, antenna-matching circuit, transport module, B40 filtering front end match circuit, B40 filtration modules, B40 filtering rear end match circuit, B41 filtering front end match circuit, B41 filtration modules, B41 filtering rear end match circuit, power amplifier module, RF transceiver and the low noise amplification module for reducing the loss of power amplifier module rear end.The utility model reduces the rear end of power amplifier module by increasing low noise amplification module in the rear end of power amplifier module and is lost, and reduces the noise factor entirely notified with this, so as to optimize the sensitivity of TDD segment sensitive degree.

Description

Mobile terminal and its control circuit for improving TDD segment sensitive degree

Technical field

The utility model is related to technical field of mobile terminals, more particularly to a kind of mobile terminal and its for improve TDD frequency The control circuit of section sensitivity.

Background technology

The mobile terminals such as smart mobile phone, in TDD_LTE（Time Division Long Term Evolution timesharing is long Phase evolution,）Pattern（That is TDD mode）Under, due to TDD（Time division duplex）Middle band40/41 band operation frequency difference For：2300MHz-2400MHz, 2496MHz-2690MHz.Under this frequency, the differential loss of path may be up to 8dB or so, and it connects Receive sensitivity behaviour poor.It is exactly hand as most directly embodying for mobile phone terminal performance in the case where receiving sensitivity is poor Machine signal difference, influences speech quality.

Thus prior art could be improved and improve.

Utility model content

The technical problems to be solved in the utility model is, in view of the shortcomings of the prior art there is provided a kind of mobile terminal and It is used for the control circuit for improving TDD segment sensitive degree, can lift Band40＆41 receiving sensitivity.

In order to solve the above-mentioned technical problem, the technical scheme that the utility model is used is as follows：

It is a kind of be used for improve mobile terminal TDD segment sensitive degree control circuit, including antenna, antenna-matching circuit, Transport module, B40 filtering front end match circuit, B40 filtration modules, B40 filtering rear end match circuit, B41 filtering front end matching Circuit, B41 filtration modules, B41 filtering rear end match circuit, power amplifier module and RF transceiver；What the antenna was received Band 40 and/or the radiofrequency signals of Band 41 are exported to transport module after optimizing through antenna-matching circuit, are switched by transport module After be divided into two-way radiofrequency signal：All the way radiofrequency signal successively through B40 filtering front end match circuit optimization, B40 filtration modules filtering, Inputted after B40 filtering rear end match circuit optimizations into power amplifier module；Another road radiofrequency signal filters front end through B41 successively Inputted after match circuit optimization, the filtering of B41 filtration modules, B41 filtering rear end match circuit optimizations into power amplifier module；Institute Stating control circuit also includes being used to reduce the low noise amplification module of power amplifier module rear end loss；The low noise amplification mould Radiofrequency signal after the amplification of block receiving power amplification module, and carry out after the rear end loss of low noise amplification reduction power amplifier module Export to RF transceiver.

In the described control circuit of TDD segment sensitive degree for improving mobile terminal, the low noise amplification module Including low noise amplification unit, difference processing unit and hollow matching unit；The radiofrequency signal warp of power amplifier module output Exported after the amplification of low noise amplification unit and give difference processing unit, single-ended signal is converted into difference letter by difference processing unit Number, and exported after the optimization of hollow matching unit to RF transceiver.

In the described control circuit of TDD segment sensitive degree for improving mobile terminal, the low noise amplification unit Including low-noise amplifier, the first electric capacity, the second electric capacity and the first inductance；The RFIN ends connection power of the low-noise amplifier Amplification module, the RFIN ends of low-noise amplifier are by the second capacity earth, and the vdd terminal of the low-noise amplifier passes through first Capacity earth, the RFOUT ends of the low-noise amplifier connect the input of difference processing unit, connect also by the first inductance Ground.

In the described control circuit of TDD segment sensitive degree for improving mobile terminal, the difference processing unit bag Include the 3rd electric capacity and balun converter；Input, its connection low noise of one end of 3rd electric capacity for difference processing unit The RFOUT ends of amplifier, the other end of the 3rd electric capacity connects the Unbalance ends of balun converter, the balun converter Balance1 ends connect the first input end of hollow matching unit, the Balance2 ends connection hollow of the balun converter Second input of matching unit.

In the described control circuit of TDD segment sensitive degree for improving mobile terminal, the hollow matching unit Including the second inductance, the 3rd inductance, the 4th electric capacity and the 5th electric capacity；One end of 4th electric capacity is hollow matching unit One end of first input end, its Balance1 end for connecting balun converter and the second inductance, the other end connection of the 4th electric capacity One end of 3rd inductance and RF transceiver；One end of 5th electric capacity for hollow matching unit the second input, its The Balance2 ends of balun converter and the other end of the second inductance are connected, the other end of the 5th electric capacity connects the another of the 3rd inductance One end and RF transceiver.

In the described control circuit of TDD segment sensitive degree for improving mobile terminal, the low-noise amplifier Model：MXD8015H.

In the described control circuit of TDD segment sensitive degree for improving mobile terminal, the type of the balun converter Number it is：RFBLN06052G5WM9T16.

A kind of mobile terminal, including terminal body, are provided with pcb board, the PCB in the terminal body The control circuit as described above for being used to improve the TDD segment sensitive degree of mobile terminal is provided with plate.

Beneficial effect：Compared with prior art, the utility model provides a kind of mobile terminal and its for improving TDD frequencies The control circuit of section sensitivity.Wherein, control circuit includes：Antenna, antenna-matching circuit, transport module, B40 filtering front end With circuit, B40 filtration modules, B40 filtering rear end match circuit, B41 filtering front end match circuit, B41 filtration modules, B41 filters Ripple rear end match circuit, power amplifier module, RF transceiver and the low noise for reducing the loss of power amplifier module rear end Amplification module；The Band 40 and/or the radiofrequency signals of Band 41 that the antenna is received exported after optimizing through antenna-matching circuit to Transport module, by transport module switch after be divided into two-way radiofrequency signal：Radiofrequency signal is successively through B40 filtering front end matching electricity all the way Inputted after road optimization, the filtering of B40 filtration modules, B40 filtering rear end match circuit optimizations into power amplifier module；Another road is penetrated Frequency signal is successively after the optimization of B41 filtering front end match circuits, the filtering of B41 filtration modules, B41 filtering rear end match circuit optimizations Input is into power amplifier module；By power amplifier module amplify after export and give low noise amplification module, and by low noise amplification Module is exported to RF transceiver after carrying out the rear end loss of low noise amplification reduction power amplifier module.The utility model passes through The rear end that power amplifier module is reduced in the rear end increase low noise amplification module of power amplifier module is lost, and is reduced with this The noise factor entirely notified, so as to optimize the sensitivity of TDD segment sensitive degree.

Brief description of the drawings

The structure of the control circuit for the TDD segment sensitive degree for being used to improve mobile terminal that Fig. 1 provides for the utility model Block diagram.

Low noise in the control circuit for the TDD segment sensitive degree for improving mobile terminal that Fig. 2 provides for the utility model The circuit diagram of sound amplification module.

Embodiment

The utility model provides a kind of mobile terminal and its control circuit for improving TDD segment sensitive degree, to make this The purpose of utility model, technical scheme and effect are clearer, clear and definite, and the embodiment that develops simultaneously referring to the drawings is to the utility model It is further described.It should be appreciated that specific embodiment described herein is not used to limit only to explain the utility model Determine the utility model.

Referring to Fig. 1, it is electric for the control for being used to improve the TDD segment sensitive degree of mobile terminal that the utility model is provided The structured flowchart on road.As shown in figure 1, the control for being used to improve the TDD segment sensitive degree of mobile terminal that the utility model is provided Circuit include antenna Y1, antenna-matching circuit 11, transport module 12, B40 filtering front end match circuit 13, B40 filtration modules 14, B40 filtering rear end match circuit 15, B41 filtering front end match circuit 16, B41 filtration modules 17, B41 filtering rear end match circuits 18th, power amplifier module 19, RF transceiver 20 and low noise amplification module 21.

The antenna Y1 connects transport module 12, the first output end of the transport module 12 by antenna-matching circuit 11 B40 filtering front end match circuit 13, B40 filtration modules 14 and the B40 filtering connection power of rear end match circuit 15 is passed sequentially through to put Big module 19, the second output end of the transport module 12 passes sequentially through B41 filtering front end match circuit 16, B41 filtration modules The 17 and B41 filtering connection power amplifier modules 19 of rear end match circuit 18, the power amplifier module 19 passes through low noise amplification Module 21 connects RF transceiver 20.

When antenna receives radiofrequency signal, the Band 40 and/or the radiofrequency signals of Band 41 that the antenna is received are through day Lines matching circuit 11 optimize after export to transport module 12, by transport module 12 switch after be divided into two-way radiofrequency signal：Penetrate all the way Through B40 filtering, front end match circuit 13 optimizes frequency signal, B40 filtration modules 14 are filtered, B40 filters rear end match circuit 15 successively Inputted after optimization into power amplifier module 19；Another road radiofrequency signal successively through B41 filtering front end match circuit 16 optimize, B41 filtration modules 17 are filtered, B41 filtering rear end match circuits 18 are inputted into power amplifier module 19 after optimizing；Put by power Big module 19 is exported to low noise amplification module 21 after amplifying, and carries out low noise amplification reduction work(by low noise amplification module 21 Exported after the rear end loss of rate amplification module 19 to RF transceiver 20.The utility model passes through after power amplifier module 19 End increase low noise amplification module 21 is lost to reduce the rear end of power amplifier module 19, reduces the noise entirely notified with this System, so as to optimize the sensitivity of TDD segment sensitive degree.

In order to ensure that TDD high frequencies Band40＆41 receiving sensitivity is more excellent, it is ensured that mobile terminal（Such as mobile phone）Receive signal Ability it is stronger, can be realized by two ways：First way, reduction power-amplifier front-end path loss, pass through Debug Band40＆41（That is B40 filtration modules 14 and B41 filtration modules 17）The match circuit parameter of front and back end optimize；The Two kinds of modes, the back-end path losses of reduction B40 filtration modules 14, by the rear end of B40 filtration modules 14, namely Band40＆41 Increase low noise amplification module 21 in receiving path to reduce the noise coefficient of whole path, so as to optimize sensitivity.

Based on above two mode, first, optimize PA（Power amplifier）The differential loss of front end path, can be by the filter of debugging The π types matching at wavefront end（I.e. regulation B40 filtering front end match circuits 13 and B41 filter the electronic component of front end match circuit 16 Parameter）, make Band40＆41 convergence circle to minimum state, convergence namely with the S11 in frequency band（Return loss）Performance, Reflect the radio-frequency performance uniformity of whole frequency band；Secondly, the π types matching of debugging filtering rear end（That is B40 filters rear end match circuit The parameter of the electronic component of 15 and B41 filtering rear end match circuits 18）, make S21（Positive transmission coefficient）Parameter is in smith circle diagrams On close to 50ohm（Can be by being found out on Network Analyzer）.Now, the insertion loss of whole PA front ends path is optimized to most Excellent level.Band40 and Band41 receiving sensitivity is respectively -95.8dBm and -95.5dBm.

Now, the limit has been arrived by debugging matching optimization sensitivity behaviour, it is impossible to continuing to improve, the utility model Same receiving circuit is used using band40 between from PA to RF transceiver 20 and band41, by PA to radio-frequency receiving-transmitting A low noise amplification module 21 is added in receiving path between device 20, according to noise coefficient cascading equations and limiting snesibility Calculation formula, it is known that now mobile terminal can neglect the loss of PA back-end paths.So, whole radio frequency reception path performance Only determined by PA front ends path loss.

The sensitivity to the band40 and band41 of mobile terminal the two frequency ranges is illustrated below：

1st, concisely it is defined as plus noise coefficient cascading equations after low noise amplification module 21：

Noise figure(dB)_All= LNA Pre-loss(dB)+LNA Noise figure(dB)

Wherein：Noise figure (dB) _ All is the total noise coefficient of path, and LNA Pre-loss are LNA（Low noise Amplifier U1）The loss of front end；LNA Noise figure are LNA bodies（That is low noise amplification module 21 itself）Noise system Number.

2nd, do not increase before LTE LNA, the noise coefficient of whole path may be calculated：

Noise figure (dB) _ All=PA front ends path loss（dB）+ PA back-end paths are lost（dB）

Wherein：LNA Pre-loss are PA front ends path loss

3rd, receiver sensitivity calculation formula：

Sen(dBm)=-174dBm/Hz+ Noise figure+10log(Rb)+SNRmini

Wherein：- 174dBm/Hz is the thermal noise floor of receiver, and Rb is GPS code rate, and SNRmini receives to receive function Minimum signal to noise ratio.

I.e. PA front ends path loss LNA Pre-loss, and the loss of PA back-end paths is because of the cabling on pcb board It is longer, typically there is 3 ~ 5dB.LNA noise coefficient is generally 0.8dB or so, so, add after LNA, LNA Noise figure <PA back-end paths are lost, and total Noise Figure diminish.Further according to the 3rd formula, Noise Figure are small, sensitive Degree is also just small, therefore the receiving sensitivity of mobile terminal is enhanced.Mobile terminal of the present utility model add LNA it Afterwards, the receiving sensitivity of two frequency ranges of band40 and band41 has respectively reached 97.5 and 97.4, and mobile phone energy is ensure that substantially Enough there is stronger signal.

Also referring to Fig. 2, when it is implemented, the low noise amplification module 21 include low noise amplification unit 211, it is poor Divide processing unit 212 and hollow matching unit 213；The input connection power amplification mould of the low noise amplification unit 211, The output end of low noise amplification unit 211 passes sequentially through difference processing unit 212 and the connection radio frequency of hollow matching unit 213 is received Send out device 20.The radiofrequency signal that power amplifier module 19 is exported exports after amplifying through low noise amplification unit 211 and gives difference processing list Member 212, differential signal is converted into by difference processing unit 212 by single-ended signal, and defeated after the optimization of hollow matching unit 213 Go out to RF transceiver 20, from signal flow direction as denoted by the arrows in fig. 2.

When it is implemented, the low noise amplification unit 211 includes low-noise amplifier U1, the first electric capacity C1, the second electricity Hold C2 and the first inductance L1；The RFIN ends connection power amplifier module 19 of the low-noise amplifier U1, low-noise amplifier U1 RFIN ends be grounded by the second electric capacity C2, the vdd terminal of the low-noise amplifier U1 is grounded by the first electric capacity C1, described low Noise amplifier U1 RFOUT ends connect the input of difference processing unit 212, are grounded also by the first inductance L1.

The difference processing unit 212 includes the 3rd electric capacity C3 and balun converter U2；One end of the 3rd electric capacity C3 For the RFOUT ends of the input of difference processing unit 212, its connection low-noise amplifier U1, the 3rd electric capacity C3 other end connects Connect balun converter U2 Unbalance ends, the Balance1 ends connection hollow matching unit 213 of the balun converter U2 First input end, the second input of the Balance2 ends connection hollow matching unit 213 of the balun converter U2.

The hollow matching unit 213 includes the second inductance L2, the 3rd inductance L3, the 4th electric capacity C4 and the 5th electric capacity C5；One end of the 4th electric capacity C4 is the first input end of hollow matching unit 213, its connection balun converter U2 Balance1 ends and the second inductance L2 one end, the 4th electric capacity C4 other end connect the 3rd inductance L3 one end and radio-frequency receiving-transmitting Device 20；One end of the 5th electric capacity C5 is the second input of hollow matching unit 213, its connection balun converter U2 Balance2 ends and the second inductance L2 other end, the 5th electric capacity C5 other end connect the 3rd inductance the L3 other end and radio frequency Transceiver 20.

In the present embodiment, the transport module 12 includes model AP6716M-31 transmission chip and its peripheral circuit, B40 filtration modules 14 include model SAFFB2G35MA0F0A filtering chip and its peripheral circuit, and B41 filtration modules 17 are wrapped Model SAFFB2G60MA0F0A filtering chip and its peripheral circuit is included, power amplifier module 19 includes model AP7219M Power amplifier chips and its peripheral circuit, RF transceiver 20 include model RFBLN06052G5WM9T16 and its peripheral circuit. The model of the low-noise amplifier U1：MXD8015H, the model of the balun converter U2： RFBLN06052G5WM9T16.Due to antenna-matching circuit 11, transport module 12, B40 filtering front end match circuit 13, B40 filters After ripple module 14, B40 filtering rear end match circuit 15, B41 filtering front end match circuit 16, B41 filtration modules 17, B41 filtering The function of holding match circuit 18, power amplifier module 19 and RF transceiver 20 is prior art, and this practicality is not made in detail to this Carefully.

In order to be better understood from the utility model, below in conjunction with Fig. 1 and Fig. 2, it is used to improve movement to of the present utility model Signal processing of the control circuit of the TDD segment sensitive degree of terminal when receiving radiofrequency signal is described in detail：

Antenna is received after Band 40 and/or the signals of Band 41, and impedance is moved to by the impedance of antenna-matching circuit 11 optimization 50ohm is loaded, and makes the impedance matching of antenna port and transport module 12.Signal after impedance optimization is from AP6716M-31 chips ANT pin are inputted, and into AP6716M-31 chip internals, are recognized the frequency range of signal through AP6716M-31 chips and are carried out internal switch Switching, is exported by AP6716M-31 chips Pin32 (B40_TRX_ASM) and Pin33 (B41_TRX_ASM) pin respectively.

Wherein, the signals of Band 40 of switching are inputted after filtering the impedance of front end match circuit 13 optimization through B40 The Unbanced2 pin of SAFFB2G35MA0F0A chips, and from the Unbanced1 pin of SAFFB2G35MA0F0A chips export to B40 filtering rear end match circuits 15 carry out impedance optimization；The signals of Band 41 of switching hinder through B41 filtering front end match circuits 16 The Unbanced2 pin of SAFFB2G60MA0F0A chips are inputted after anti-optimization, and from SAFFB2G60MA0F0A chips Unbanced1 pin export to B41 filtering rear end match circuits 18 and carry out impedance optimization.

The signals of Band 40 and the signals of Band 41 filter rear end match circuit 15 and B41 filtering rear end matching through B40 respectively After the impedance of circuit 18 optimization, Band40 signals input Pin35 (HB2) pin of AP7219M chips, the input of Band41 signals Pin33 (HB1) pin of AP7219M chips, is then uniformly switched to P42 from the 3P4T switches of AP7219M chip internals （HBRX2）Pin, is exported to the input of MXD8015H chips by P42 pin（RFIN ends）, low noise is carried out through MXD8015H chips After sound amplification, and it is output to from RFOUT ends the unbalanced pin of RFBLN06052G5WM9T16 chips, warp Single-ended signal is converted into after differential signal by RFBLN06052G5WM9T16 chips, and it is excellent to carry out impedance through hollow match circuit Change, be output to the LTE_RFIN_HB3 pin in MT6169 chips.

Substantially the above-mentioned control circuit for being used to improve the TDD segment sensitive degree of mobile terminal, the utility model is also corresponding A kind of mobile terminal, including terminal body are provided, are provided with the terminal body on pcb board, the pcb board It is provided with the control circuit of the TDD segment sensitive degree for improving mobile terminal.Due to being carried out to the control circuit above It is described in detail, here is omitted.

In summary, the utility model make use of the switch inside power amplifier, and band40 and band4 frequencies are used Same receiving path transmits a signal to RF transceiver, and adds in its receiving path a low noise amplification mould Block, while improving the receiving sensitivity of band40＆band41 frequencies.The purpose for improving receiving sensitivity has not been only reached, and Only with a low noise amplification module, cost is saved.

Finally it should be noted that：Above example is only to illustrate the technical solution of the utility model, rather than its limitations； Although the utility model is described in detail with reference to the foregoing embodiments, it will be understood by those within the art that： It can still modify to the technical scheme described in foregoing embodiments, or which part technical characteristic is carried out etc. With replacement；And these modifications or replacement, the essence of appropriate technical solution is departed from each embodiment technology of the utility model The spirit and scope of scheme.

Claims

1. a kind of control circuit for being used to improve the TDD segment sensitive degree of mobile terminal, it is characterised in that including antenna, antenna Match circuit, transport module, B40 filtering front end match circuit, B40 filtration modules, B40 filtering rear end match circuit, B41 filtering Front end match circuit, B41 filtration modules, B41 filtering rear end match circuit, power amplifier module and RF transceiver；The day The Band 40 and/or the radiofrequency signals of Band 41 that line is received are exported to transport module after optimizing through antenna-matching circuit, by transmitting It is divided into two-way radiofrequency signal after module switching：Radiofrequency signal is filtered through the optimization of B40 filtering front end match circuits, B40 successively all the way Inputted after module filtered, B40 filtering rear end match circuit optimizations into power amplifier module；Another road radiofrequency signal is passed through successively Input to power and put after the optimization of B41 filtering front end match circuits, the filtering of B41 filtration modules, B41 filtering rear end match circuit optimizations In big module；The control circuit also includes being used to reduce the low noise amplification module of power amplifier module rear end loss；It is described Radiofrequency signal after the amplification of low noise amplification module receiving power amplification module, and carry out low noise amplification reduction power amplifier module Rear end loss after export to RF transceiver.

2. the control circuit according to claim 1 for being used to improve the TDD segment sensitive degree of mobile terminal, its feature exists In the low noise amplification module includes low noise amplification unit, difference processing unit and hollow matching unit；Power amplification The radiofrequency signal of module output exports after amplifying through low noise amplification unit and gives difference processing unit, will be single by difference processing unit End signal is converted into differential signal, and is exported after the optimization of hollow matching unit to RF transceiver.

3. the control circuit according to claim 2 for being used to improve the TDD segment sensitive degree of mobile terminal, its feature exists In the low noise amplification unit includes low-noise amplifier, the first electric capacity, the second electric capacity and the first inductance；The low noise The RFIN ends connection power amplifier module of amplifier, the RFIN ends of low-noise amplifier pass through the second capacity earth, the low noise The vdd terminal of acoustic amplifier connects the defeated of difference processing unit by the first capacity earth, the RFOUT ends of the low-noise amplifier Enter end, be grounded also by the first inductance.

4. the control circuit according to claim 3 for being used to improve the TDD segment sensitive degree of mobile terminal, its feature exists In the difference processing unit includes the 3rd electric capacity and balun converter；One end of 3rd electric capacity is difference processing unit Input, its connect the RFOUT ends of low-noise amplifier, the other end connection balun converter of the 3rd electric capacity Unbalance ends, the Balance1 ends of the balun converter connect the first input end of hollow matching unit, the balun The Balance2 ends of converter connect the second input of hollow matching unit.

5. the control circuit according to claim 4 for being used to improve the TDD segment sensitive degree of mobile terminal, its feature exists In the hollow matching unit includes the second inductance, the 3rd inductance, the 4th electric capacity and the 5th electric capacity；4th electric capacity One end is the one of the first input end of hollow matching unit, its Balance1 end for connecting balun converter and the second inductance End, the other end of the 4th electric capacity connects one end and the RF transceiver of the 3rd inductance；One end of 5th electric capacity is hollow The other end of second input of matching unit, its Balance2 end for connecting balun converter and the second inductance, the 5th electric capacity The other end connect the 3rd inductance the other end and RF transceiver.

6. the control circuit according to claim 2 for being used to improve the TDD segment sensitive degree of mobile terminal, its feature exists In the model of the low-noise amplifier：MXD8015H.

7. the control circuit according to claim 4 for being used to improve the TDD segment sensitive degree of mobile terminal, its feature exists In the model of the balun converter：RFBLN06052G5WM9T16.

8. a kind of mobile terminal, including terminal body, pcb board is provided with the terminal body, its feature exists In being set on the pcb board and improve the TDD segment sensitives of mobile terminal just like being used for described in claim 1-7 any one The control circuit of degree.