TWI448132B - Time division duplexing control and protective device and method thereof - Google Patents

Description

Time division duplex control and protection device and method thereof

The present invention provides a time division duplex control and protection device, particularly for use in a remote antenna unit in a time division duplex wireless-fiber system.

In recent years, Radio over Fiber (RoF) has been actively researched by various academic and research institutions around the world, especially through the wireless-fiber system distributed remote antenna unit (RAU). The coverage of broadband wireless networks such as Worldwide Interoperability for Microwave Access (WiMAX), Long Term Evolution (LTE), and the like is increased and the cost of construction is reduced.

In the wireless-fiber system, the signal under the broadband wireless network is transmitted from the base station to the remote antenna unit via the downlink loop, and then the remote antenna unit transmits the downlink signal to the user equipment (such as a mobile phone), and The uplink signal sent back from the user equipment is received by the remote antenna unit, and the uplink signal is transmitted to the base station by the uplink circuit. Among them, since the downlink signal is transmitted to all users in the area, the power of the downlink signal is much larger than the power of the uplink signal.

In the Time Division Duplexing (TDD) wireless-fiber system, since the power of the downlink signal is much larger than the power of the uplink signal, when the signal is transmitted, the downlink signal may pass through the uplink circuit and cause circuit damage. The current practice is to set a switch between the downlink loop and the uplink loop, and a controller controls the switch between the downlink loop and the uplink loop according to the downlink signal, that is, when the downlink signal is transmitted, the uplink loop is opened, and when the uplink signal is transmitted, Open the downlink circuit to avoid circuit damage caused by the downlink signal passing through the uplink circuit.

However, when the downlink signal is interfered by noise, it will often cause the controller. The malfunction occurs, and the switch between the downlink loop and the uplink loop does not operate normally, causing the downlink signal to pass through the uplink loop and causing circuit damage.

In addition, the remote antenna unit is often placed in a relatively remote or difficult to maintain area, so when the circuit is not working properly or damaged, it is difficult for the maintenance personnel to repair the system immediately, which will interrupt the signal communication and cause the user to inconvenient.

Therefore, the development of a method or device that can solve the above-mentioned deficiencies is an urgent problem to be solved.

Accordingly, the present invention is to solve the above-mentioned shortcomings of the prior art, and aims to provide a time-division duplex control and protection device for detecting the duty cycle of a signal under actual transmission to determine whether the downlink signal is interfered by noise, and Various conditions determine the output control signal to control the switch between the upper and lower loops to avoid mutual interference between the upstream and downstream loops, or the downlink signal causes circuit damage via the uplink loop.

For the purpose of the present invention, a time division duplex control and protection device is provided, which is disposed in a remote antenna unit in a time division duplex wireless-fiber system, and the remote antenna unit transmits a downlink signal and receives an uplink signal. The time-division duplex control and protection device controls at least one switch of the remote antenna unit according to the downlink signal, so that the downlink signal and the uplink signal are completely turned on, partially turned on or not turned on at all, and the time division duplex control and protection device The utility model comprises: a plurality of switch control signal generating circuits, a start signal determining circuit, a duty cycle calculating circuit and a duty cycle adjusting circuit. A plurality of switch control signal generating circuits are respectively connected to at least one switch of the remote antenna unit, and output a plurality of control signals to respectively control at least one switch. The start signal decision circuit is used to determine whether the downlink signal transmission has started. The duty cycle calculation circuit is electrically connected to the start signal determination circuit, and is used for calculating the duty cycle of the downlink signal, and has a preset Referring to the work cycle, the work cycle calculation circuit is configured to compare with the working cycle of the downlink signal according to the reference duty cycle, and if the comparison to the work cycle does not match the reference duty cycle, output a plurality of first control signals to The plurality of switch control signal generating circuits cause the plurality of switch control signal generating circuits to output a plurality of switch control signals to control the at least one switch to operate in the first mode. The duty cycle adjustment circuit is electrically connected to the duty cycle calculation circuit. When the comparison to the duty cycle is consistent with the reference duty cycle, the duty cycle adjustment circuit will adjust the duty cycle of the downlink signal, and will adjust the signal after the downlink signal The plurality of second control signals are output to the plurality of switch control signal generating circuits, so that the plurality of switch control signal generating circuits output a plurality of switch control signals to control the at least one switch to operate in the second mode.

In order to achieve the object of the present invention, another method for time division duplex control and protection is provided, which is applicable to a remote antenna unit in a time division duplex wireless-fiber system, and the remote antenna unit transmits a downlink signal and receives The uplink signal, the time division duplex control and protection method comprises: receiving the downlink signal in the time division duplex wireless-fiber system, and the downlink signal has a duty cycle; a start signal determining circuit determines whether the downlink signal transmission has started Calculating the working period of the downlink signal, and comparing the working period of the downlink signal by using a preset reference working period; controlling the at least one of the remote antenna units when the comparison to the working period does not match the reference working period; a switch is operated in the first mode; and when the comparison to the duty cycle coincides with the reference duty cycle, adjusting the duty cycle of the downlink signal, and controlling at least one of the remote antenna units according to the adjusted downlink signal The switch is actuated in the second mode. .

Therefore, the present invention can make the remote antenna unit in the duplex wireless-fiber system at the time of scoring have the function of self-protection, and can make the remote antenna unit be disposed in various regions to expand the coverage of the signal and reduce the construction. Set the cost.

Embodiments of the present invention will be described below with reference to the accompanying drawings. In the following description, the same elements will be designated by the same elements, even if they are in different drawings. Further, the known functions and features of the present invention are omitted in the following description of the present invention to avoid confusion with the subject matter of the present invention.

Further, in the description of the elements of the present invention, for example, the first, second, A, B, (a), (b) or other similar terms and labels are used. However, the terms are not intended to define the nature, order, or permutation of the corresponding elements, but only to distinguish them from other elements. Please note that in the description, when an element is “coupled”, “connected” or “coupled” to another element, it is meant that the first element may directly “couple”, “connect”, “join” to the second element. It is also indicated that there may be a third element "combined", "connected", "joined" between the first and second elements.

Please refer to FIG. 1. FIG. 1 is a circuit block diagram of a time division duplex wireless-fiber system according to an embodiment of the present invention. As shown, the time division duplex wireless-fiber system 100 of the present embodiment includes a base station 101, a head end unit 103, a downlink optical fiber network 105a, an upstream optical network 105b, and a remote antenna unit 107. In this embodiment, a first electro-optic (E/O) converter 1031 and a first optoelectronic (O/E) converter 1032 are disposed in the head end unit 103. The remote antenna unit 107 is provided with a time division duplex control and protection device 108, a second photoelectric (O/E) converter 1071, a second electro-optical (E/O) converter 1072, a power amplifier 1073, and a low noise amplifier. 1074, switch X1 and antenna 109. In this embodiment, the first electro-optic (E/O) converter 1031 and the second electro-optic (E/O) converter 1072 may be, but not limited to, a laser diode (Laser Diode), and the first photo-electricity (O The /E) converter 1032 and the second optoelectronic (O/E) converter 1071 may be, but not limited to, a photodiode.

The time-division duplex wireless-fiber system 100 transmits the broadband wireless network to the user as the downlink signal S _d , and the downlink signal S _d is transmitted from the base station 101 to the head unit 103, and the downlink signal S _d For the telecommunication number. The downlink signal S _{d is} converted into the downlink optical signal S _do by the first electro-optical (E/O) converter 1031 in the head end unit 103 and transmitted to the remote antenna unit 107 via the downlink optical fiber network 105a. The second optoelectronic (O/E) converter 1071 in the remote antenna unit 107 converts the downlink optical signal S _do into a signal signal S _d . The power amplifier 1073 is configured to amplify the power of the downlink signal S _d and then transmit it to the user equipment (such as a mobile phone) by the antenna 109, which is the path of the downlink loop.

When the antenna 109 receives signals from the user equipment (i.e. the uplink signal), the antenna 109 will be transmitted to an uplink signal S _u LNA 1074, 1074 by the LNA signal S _u of an uplink signal amplifier Passed to a second electro-optic (E/O) converter 1072. The second electro-optical (E/O) converter 1072 converts the uplink signal S _u into an upstream optical signal S _uo and transmits it to the head end unit 103 via the upstream optical network 105b. The head end unit 103 of the first photoelectric (O / E) converter 1032 based uplink optical signal train is converted into S _uo uplink signal S _u of the electric signal, an uplink signal S _u then transmitted to the base station, that is, for The path of the upstream loop. In this way, the signal transmission and reception of the time division duplex wireless-fiber system 100 can be completed.

Since the downlink signal S _d is amplified by the power amplifier 1073 and then transmitted through the antenna 109, the power of the downlink signal S _d is extremely large after the power is amplified, and therefore must be added between the power amplifier 1073 and the low noise amplifier 1074. The switch X1 is connected to the antenna 109 through the switch X1, that is, the switch X1 can selectively conduct the power amplifier 1073 and the antenna 109 or turn on the low noise amplifier 1074 and the antenna 109. In this way, the downlink signal S _d is prevented from passing through the uplink circuit and destroying the low noise amplifier 1074, thereby causing circuit damage. For example, the downlink signal S _d destroys the condition of the low noise amplifier 1074. In this embodiment, the switch X1 can be a radio frequency switch.

In this embodiment, the time division duplex control and protection device 108 is configured to control the second optoelectronic (O/E) converter 1071 and the second electro-optical (E/O) converter 1072 according to the downlink signal S _d . Switch X1 to avoid circuit damage caused by mutual interference between the upper and lower loops.

The operation of the time division duplex control and protection device 108 will be described in detail below with reference to Figs. 2 and 3 and Fig. 4 . 2 is a circuit block diagram of a time division duplex control and protection device according to an embodiment of the present invention in a first state; FIG. 3 is a diagram showing a time division duplex control and protection device according to an embodiment of the present invention; FIG. 4 is a block diagram of a circuit block in a second state according to an embodiment of the present invention.

As shown in FIG. 2, the time division duplex control and protection device 108 of the present embodiment includes a power detector 1081, a signal comparison circuit 1082, a start signal decision circuit 1083, a duty cycle calculation circuit 1084, a duty cycle adjustment circuit 1085, And a first switch control signal generating circuit 1086 and a second switch control signal generating circuit 1087. In this embodiment, the first switch control signal generating circuit 1086 may be an electro-optical (E/O)/photoelectric (O/E) switch control signal generating circuit, and the second switch control signal generating circuit 1087 may be a radio frequency switch control signal. Generate a circuit.

In this embodiment, the downlink signal S _d is transmitted by the base station, so the preset working period of the downlink signal S _d can be preset by the setter, and the packet waveform of the downlink signal waveform S _d is as shown in FIG. 4 . A is shown. However, during the actual transmission of the signal, the duty cycle T _{1 of the} downlink signal S _d may be affected by the noise, so that it does not match the preset duty cycle. In addition, according to the principle of time division duplexing, the present invention only needs to detect the duty cycle T _{1 of the} downlink signal S _d , and can calculate the duty cycle T ₂ of the uplink signal S _u , so the time division duplex in this embodiment The control and protection device 108 only needs to be actuated according to the downlink signal S _d .

The second photoelectric (O/E) converter 1071 converts the downstream optical signal S _do into a signal type S _d below the analog signal. Power detector 1081 is used for receiving such signal lines than under the form of S _d, and the packet signal waveform acquired under the analog signal S _d in the form of rows, and the rows below the analog signal S _d based form having a duty cycle T _1, the downlink case The waveform of the signal waveform S _d will be as shown in B of Fig. 4. The signal comparison circuit 1082 is electrically coupled to the power detector 1081 to convert the analog signal S _{d from the} analog form to the signal type S _d under the digital signal. At this time, the duty cycle T ₁ of the row signal S _d under the digit form is still the same as the duty cycle T ₁ of the row signal S _d under the analog form. In addition, the waveform of the downlink signal waveform S _d at this time is as shown by C in FIG. 4 . Starting signal-based determination circuit 1083 and comparator circuit 1082 electrically connected to the signal for a limited time in _a row in one of the duty cycle signal S _d of the T under the digital form, to retrieve rows under the digital form signal S _d. In this embodiment, defines a time-based duty cycle is set to half the period T _1, in a limited time if the retrieved bit value is 1, i.e., the line determination signal S _d is transmitted under the digital form has been initiated.

The duty cycle calculation circuit 1084 is electrically coupled to the start signal decision circuit 1083 for calculating the duty cycle T _{1 of the} actually transmitted digital signal of the downlink signal S _d and is provided with a preset reference duty cycle. In this embodiment, the reference duty cycle can be the same as the preset duty cycle. The duty cycle calculation circuit 1084 compares with the duty cycle T ₁ of the row signal S _d under the digital form according to the reference duty cycle. Once the comparison to the duty cycle T ₁ does not match the reference duty cycle (ie, the first state), Then, the first control signal S _{c1 is} output to the first switch control signal generating circuit 1086 and the second switch control signal generating circuit 1087. In this embodiment, the first switch control signal generating circuit 1086 generates the first switch control signal S ₁ based on the first control signal S _c1 , and the second switch control signal generating circuit 1087 is based on the first control signal S _{c1 .} , to generate a second switch control signal S ₂ . The first switch control signal S ₁ controls the second photoelectric (O/E) converter 1071 and the second electro-optical (E/O) converter 1072 to operate in the first mode, in this embodiment, the second The operation of the optoelectronic (O/E) converter 1071 and the second electro-optical (E/O) converter 1072 in the first mode may be off. The second switch control signal S ₂ is forcibly controlling the switch X1 to operate in the first mode. In this embodiment, the switch X1 is activated in the first mode and may be an open circuit. In this way, the upper and lower loops can be isolated to avoid noise interference of the circuit, so that the downlink signal S _d passes through the uplink loop and causes circuit damage. When in the first state, the duty cycle adjusting circuit 1085 does not operate, and does not output a control signal to control the first switch control signal generating circuit 1086 and the second switch control signal generating circuit 1087.

In other embodiments, the duty cycle calculation circuit 1084 is provided with a malfunction detection circuit 1084a, and the preset reference duty cycle is set in the fault detection circuit 1084a. Duty cycle calculation circuit 1084 calculates the number of bits in the form of actually transmitted the downlink signal the duty cycle S _d of T after _1, the malfunction detecting circuit 1084a based on the reference duty cycle to match under digital form row signal S _d of the work The period T ₁ , once the comparison to the duty cycle T ₁ does not match the reference duty cycle (ie, the first state), the command duty cycle calculation circuit 1084 outputs the first control signal S _c1 to the first switch control signal generating circuit 1086 and the first The second switch control signal generating circuit 1087.

In this embodiment, the first switch control signal generating circuit 1086 generates a first switch control signal S ₁ based on the first control signal S _c1 , and the second switch control signal generating circuit 1087 is based on the first control signal S _{c1 .} And generating a second switch control signal S ₂ . The first switch control signal S ₁ controls and forces the second photoelectric (O/E) converter 1071 and the second electro-optical (E/O) converter 1072 to be turned off (ie, the first mode). The second switch control signal S ₂ is forcibly controlling the switch X1 to open (ie, the first mode). In this way, the upper and lower loops can be isolated to avoid noise interference of the circuit, and the downlink signal S _d passes through the uplink loop and causes circuit damage. In some or other embodiments, in the first state, a second switch control signal generation circuit 1087 is controlled to produce a second switching control signal S _2, the control system switches to the first mode so as X1 movable perishable. In other embodiments, even if the low noise amplifier 1074 and the power amplifier 1073 and the antenna 109 remain open, the switch X1 operates in the first mode, forcing the control switch X1 to conduct only the power amplifier 1073 and the antenna 109. . In this way, the downlink signal S _d will be transmitted from the downlink loop to the antenna 109 and then transmitted to the user in the area. This can also prevent the downlink signal S _{d from} going through the uplink loop and causing circuit damage.

Referring to FIG 3, if the comparison to the duty cycle T ₁ conformity with the reference duty cycle (i.e., second state), which represents no noise interference circuit. The duty cycle adjustment circuit 1085 will adjust the duty cycle T ₁ of the digital signal of the downlink signal S _d to generate a plurality of second control signals S _c2 . And the plurality of second control signals S _c2 have a duty cycle T ₁ '. In this embodiment, the duty cycle adjustment circuit 1085 delays the duty cycle T ₁ of the digital signal of the downlink signal S _d by a delay time, wherein the delay time is based on a half cycle that does not exceed the duty cycle T ₁ . Subsequently, the number of bits in the form of a delay of a downlink signal S _d, and under the original digital form row signal S _d are superposed (this case downstream signal waveform S _d of the waveform in a superimposed manner as Fig. 4 D) so as to obtain a duty cycle The second control signal S _{c2 of} T ₁ ', the waveform of the downlink signal waveform S _d will be as shown in E of FIG. 4 . The second control signal S _c2 can control the first switch control signal generating circuit 1086 and the second switch control signal generating circuit 1087, so that the first switch control signal generating circuit 1086 and the second switch control signal generating circuit 1087 are The second control signal S _c2 generates a third switch control signal S ₃ and a fourth switch control signal S ₄ .

The third switch control signal S ₃ can control the second photoelectric (O/E) converter 1071 and the second electro-optical (E/O) converter 1072 according to the duty cycle T ₁ ' of the second control signal S _c2 In the second mode, in this embodiment, the second mode is that the second photoelectric (O/E) converter 1071 is turned on when the downlink signal S _{d is} transmitted, and the second electro-optical (E/O) converter 1072 is When the uplink signal S _{u is} transmitted, the second photoelectric (O/E) converter 1071 is turned off, and the second electro-optical (E/O) converter 1072 is turned on. The fourth switch control signal S ₄ can control the switch X1 to operate in the second mode according to the duty cycle T ₁ ' of the second control signal S _c2 . In this embodiment, the second mode enables the switch X1 to be selectively The power amplifier 1073 is electrically connected to the antenna 109, or the low noise amplifier 1074 and the antenna 109 are turned on, that is, the power amplifier 1073 and the antenna 109 are turned on when the downlink signal S _{d is} transmitted, and is made when the uplink signal _{Su is} transmitted. The low noise amplifier 1074 is electrically connected to the antenna 109. In this way, mutual interference between the uplink and downlink circuits can be avoided, or the downlink signal S _d can cause circuit damage through the uplink circuit.

Referring to FIG. 5 and FIG. 1 to FIG. 4, FIG. 5 is a flow chart showing a method for time division duplex control and protection according to an embodiment of the present invention.

In step 501, the power detector 1081 is used to receive the analog signal S _d of the analog form in the time-division duplex wireless-fiber system 100, and obtain the signal packet waveform thereof, and the downlink signal S _d has a duty cycle T ₁ .

In step 502, the signal comparison circuit 1082 converts the analog signal S _{d from the} analog form to the digital signal S _d .

In step 503, the start signal determining circuit 1083 determines whether the transmission of the downlink signal S _{d in} the digital form has started. When the start signal determining circuit 1083 wants to determine whether the digital signal S _d has started. , based on the time line defining the duty cycle of the signal S _d in the T ₁ under the digital form, under the capturing digital signal S _d in rows, in a limited time if the retrieved bit value is 1, i.e., determines the number of bits in the form of The downlink signal S _d delivery has started.

In step 504, the duty cycle calculation circuit 1084 is used to calculate the duty cycle T ₁ of the row signal S _d under the digital form, and the reference work cycle preset by the duty cycle calculation circuit 1084, and the digital form. The duty cycle T ₁ of the downlink signal S _d is compared.

In this embodiment, if the duty cycle T ₁ of the row signal S _d below the digital form is not matched with the reference duty cycle (ie, the first state), the first control signal S _{c1 is} output to the first switch. The control signal generating circuit 1086 and the second switch control signal generating circuit 1087. In this embodiment, the first switch control signal generating circuit 1086 generates a first switch control signal S ₁ based on the first control signal S _c1 , and the second switch control signal generating circuit 1087 is based on the first control signal S _C1 generates a second switch control signal S ₂ . The first switch control signal S ₁ controls the second photoelectric (O/E) converter 1071 and the second electro-optical (E/O) converter 1072 to be equal to the first mode of operation, in this embodiment, the second The operation of the optoelectronic (O/E) converter 1071 and the second electro-optical (E/O) converter 1072 in the first mode may be off. The second switch control signal is used to control the switch X1 to operate in the first mode. In this embodiment, the action of the switch X1 in the first mode may be an open circuit. In this way, the upper and lower loops can be isolated to avoid noise interference of the circuit, and the downlink signal S _d passes through the uplink loop and causes circuit damage.

In other embodiments, the duty cycle calculation circuit 1084 is provided with a malfunction detection circuit 1084a, and the preset reference duty cycle is set in the fault detection circuit 1084a. The duty cycle calculation circuit 1084 calculates the duty cycle of the signal S _d under the digital form according to the reference duty cycle after calculating the duty cycle T ₁ of the actually transmitted digital signal of the downlink signal S _d . T ₁ performs an alignment. Once the comparison to the duty cycle T ₁ does not match the reference duty cycle (ie, the first state), the command duty cycle calculation circuit 1084 outputs the first control signal S _c1 to the first switch control signal generation. The circuit 1086 and the second switch control signal generating circuit 1087. In this embodiment, the first switch control signal generating circuit 1086 generates the first switch control signal S ₁ based on the first control signal S _c1 , and the second switch control signal generating circuit 1087 is based on the first control signal S _c1 generates a second switch control signal S ₂ . The first switch control signal S ₁ controls and forces the second photoelectric (O/E) converter 1071 and the second electro-optical (E/O) converter 1072 to be turned off (ie, the first mode), and the second switch controls. The signal S ₂ is forcibly controlling the switch X1 to open (ie, the first mode). In this way, the upper and lower loops can be isolated to avoid noise interference of the circuit, and the downlink signal Sd passes through the uplink loop and causes circuit damage. In some or other embodiments, in the first state, a second switch control signal generation circuit 1087 is controlled to produce a second switching control signal S _2, the control system switches to the first mode so as X1 movable perishable. In other embodiments, the switch X1 in the first mode is forcibly controlling the switch X1 to turn on only the power amplifier 1073 and the antenna 109, even if the low noise amplifier 1074 is open to the power amplifier 1073 and the antenna 109. In this way, the downlink signal S _d will be transmitted from the downlink loop to the antenna 109 and then transmitted to the user in the area. This method can also prevent the downlink signal S _{d from} passing through the uplink loop and causing circuit damage.

In step 505, if the comparison to _a reference duty cycle matches the duty cycle T of the (i.e., second state), the use of the duty cycle adjusting circuit 1085 adjusts the digital form of the downlink signal the duty cycle S _d of T _1, and the duty cycle the form of the digital adjustment circuit 1085 will adjust itself accordingly the downlink signal S _d, and outputs the second control signal S _c2, the second control signal S _c2 system may control the first switch control signal generation circuit 1086 and the second switch control signal is generated The circuit 1087 is configured to cause the first switch control signal generating circuit 1086 and the second switch control signal generating circuit 1087 to generate the third switch control signal S ₃ and the fourth switch control signal S ₄ according to the second control signal S _c2 .

In this embodiment, when the duty cycle adjustment circuit 1085 is to adjust the duty cycle T ₁ of the row signal S _d under the digital form, the duty cycle adjustment circuit 1085 delays the row signal S _d under the digital form by a delay time, and then delays under the form of a digital signal S _d and the line below the original digital signal S _d in the form of superimposed rows, so as to obtain a duty cycle T ₁ 'of the second control signal S _c2.

The third switch control signal S ₃ can control the second optoelectronic (O/E) converter 1071 and the second electro-optical (E/O) converter 1072 according to the duty cycle T ₁ ' of the second control signal S _c2 , respectively. In the second mode, in the second mode, the second photoelectric (O/E) converter 1071 is turned on when the downlink signal S _{d is} transmitted, and the second electro-optical (E/O) converter 1072 is turned off. When the signal S _{u is} transmitted, the second photoelectric (O/E) converter 1071 is turned off, and the second electro-optical (E/O) converter 1072 is turned on. The fourth switch control signal S ₄ can control the switch X1 to operate in the second mode according to the duty cycle T ₁ ' of the second control signal S _c2 . In this embodiment, the second mode enables the switch X1 to selectively enable the power. The amplifier 1073 is electrically connected to the antenna 109, or the low noise amplifier 1074 and the antenna 109 are turned on, that is, when the downlink signal S _{d is} transmitted, the power amplifier 1073 and the antenna 109 are turned on, and when the uplink signal S _{u is} transmitted, the low noise amplifier 1074 is enabled. It is electrically connected to the antenna 109. In this way, mutual interference between the uplink and downlink circuits can be avoided, or the downlink signal S _d can cause circuit damage via the uplink circuit.

In summary, the time-division duplex control and protection device of the present invention can determine whether the downlink signal is interfered by noise by detecting the working period of the signal under actual transmission, and determines the output control signal according to various conditions. To control the switch between the upper and lower loops to avoid mutual interference between the upstream and downstream loops, or the downlink signal causes damage to the circuit via the uplink loop. In this way, even if the remote antenna unit is placed in a remote or unsustainable area, it can have a self-protection function.

In addition, the terms "including", "comprising" and "having" as used throughout the specification and subsequent claims are an open term and should be interpreted as "including but not limited to". Many technical and technological lexicons cited It is understood that a particular component is known to those of ordinary skill in the art. If the terms are not clearly defined in the specification, the definitions of terms that are commonly used may be interpreted according to the meaning of the dictionary, constructed and equivalent to the relevant description in the context, and should not be limited by the meaning of the model or over-standardization in the dictionary.

The above description is only a preferred embodiment of the present invention, and it should be noted that those skilled in the art can also make several improvements and retouchings without departing from the principles of the present invention. These improvements and retouchings should also be considered. It is the scope of protection of the present invention.

100‧‧‧Time-division duplex wireless-fiber system

101‧‧‧ base station

103‧‧‧ head unit

105a‧‧‧Down fiber network

105b‧‧‧Upstream optical network

107‧‧‧Remote antenna unit

1071‧‧‧Second Optoelectronic (O/E) Converter

1072‧‧‧Second electro-optic (E/O) converter

1073‧‧‧Power Amplifier

1074‧‧‧Low noise amplifier

1031‧‧‧First electro-optical (E/O) converter

1032‧‧‧First Photoelectric (O/E) Converter

108‧‧‧Time-division duplex control and protection device

1081‧‧‧Power Detector

1082‧‧‧Signal comparison circuit

1083‧‧‧Start signal decision circuit

1084‧‧‧Work cycle calculation circuit

1085‧‧‧Work cycle adjustment circuit

1086‧‧‧First switch control signal generation circuit

1087‧‧‧Second switch control signal generation circuit

109‧‧‧Antenna

X1‧‧‧ switch

S _d ‧‧‧down signal

S _do ‧‧‧Down optical signal

S _u ‧‧‧Uplink signal

S _uo ‧‧‧Upstream optical signal

T ₁ ‧‧‧ work cycle

T ₂ ‧‧‧ work cycle

T ₁ '‧‧‧ work cycle

S _c1 ‧‧‧First control signal

S _c2 ‧‧‧second control signal

S ₁ ‧‧‧First switch control signal

S ₂ ‧‧‧Second switch control signal

S ₃ ‧‧‧third switch control signal

S ₄ ‧‧‧fourth switch control signal

Step 501 to step 505

The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. FIG. 1 is a diagram showing a circuit of a time division duplex wireless-fiber system according to an embodiment of the present invention. FIG. 2 is a block diagram showing a time division duplex control and protection device in a first state according to an embodiment of the present invention; and FIG. 3 is a diagram showing time division duplex control according to an embodiment of the present invention; FIG. 4 is a circuit diagram of a circuit block in a second state according to an embodiment of the present invention; FIG. 5 is a diagram showing a time-division waveform according to an embodiment of the present invention; Flow chart of methods for control and protection.

105a‧‧‧Down fiber network

105b‧‧‧Upstream optical network

107‧‧‧Remote antenna unit

1071‧‧‧Second Optoelectronic (O/E) Converter

1072‧‧‧Second electro-optic (E/O) converter

1073‧‧‧Power Amplifier

1074‧‧‧Low noise amplifier

108‧‧‧Time-division duplex control and protection device

1081‧‧‧Power Detector

1082‧‧‧Signal comparison circuit

1083‧‧‧Start signal decision circuit

1084‧‧‧Work cycle calculation circuit

1085‧‧‧Work cycle adjustment circuit

1086‧‧‧First switch control signal generation circuit

1087‧‧‧Second switch control signal generation circuit

109‧‧‧Antenna

X1‧‧‧ switch

S _d ‧‧‧down signal

S _do ‧‧‧Down optical signal

S _u ‧‧‧Uplink signal

S _uo ‧‧‧Upstream optical signal

S _c2 ‧‧‧second control signal

S ₃ ‧‧‧third switch control signal

S ₄ ‧‧‧fourth switch control signal

Claims (14)

A time-division duplex control and protection device is disposed in one of the remote antenna units in a time-division duplex wireless-fiber system, and the remote antenna unit transmits a downlink signal and receives an uplink signal. The time duplex control and protection device controls at least one switch of the remote antenna unit according to the downlink signal, so that the downlink signal and the uplink signal are completely turned on, partially turned on or not turned on at all, and the time division duplex control And the protection device includes: a plurality of switch control signal generating circuits respectively connected to the at least one switch of the remote antenna unit, which outputs a plurality of control signals to respectively control the at least one switch; a start signal determination a circuit for determining whether the downlink signal transmission has started; a duty cycle calculation circuit electrically connected to the start signal determination circuit, and configured to calculate a duty cycle of the downlink signal, and having a preset a reference work cycle, the work cycle calculation circuit is configured to perform the work week of the downlink signal according to the reference work cycle And comparing, if the working period is not consistent with the reference working period, outputting a plurality of first control signals to the plurality of switch control signal generating circuits, so that the plurality of switch control signal generating circuits output The plurality of switch control signals to control the at least one switch to operate in a first mode; and a duty cycle adjustment circuit electrically connected to the duty cycle calculation circuit, when compared to the duty cycle When the reference working period is matched, the duty cycle adjusting circuit adjusts the working period of the downlink signal, and outputs a plurality of second control signals to the plurality of switch control signals according to the adjusted downlink signal. a circuit, wherein the plurality of switch control signal generating circuits output the plurality of switch control signals to control the at least one switch Acting in the second mode. The time division duplex control and protection device according to claim 1, wherein a signal comparison circuit is disposed in front of the start signal determination circuit, and the signal comparison circuit is configured to convert the downlink signal by analogy. In digital form. The time-division duplex control and protection device according to claim 2, wherein the start signal determining circuit captures the downlink signal in the digital form within a limited time of the working period, if The bit value taken in the limited time is 1, that is, the transmission of the downlink signal is determined to have started. The time division duplex control and protection device according to claim 1, wherein the work cycle calculation circuit is provided with a malfunction detection circuit, and the reference duty cycle is built in the malfunction detection circuit. When the working cycle does not match the reference working cycle, the malfunction detecting circuit commands the duty cycle calculating circuit to output the plurality of first control signals to the plurality of switch control signal generating circuits. The time division duplex control and protection device of claim 1, wherein the time division duplex wireless-fiber system has a downlink circuit and an uplink circuit for transmitting the downlink signal and the uplink signal respectively. And when the at least one switch is activated in the first mode, the at least one open relationship causes the downlink loop and the uplink loop to be open, even if the downlink signal and the uplink signal are in a completely non-conducting state. The time division duplex control and protection device of claim 1, wherein the time division duplex wireless-fiber system has a downlink circuit and an uplink circuit for transmitting the downlink signal and the uplink signal respectively. When the at least one switch is activated in the first mode, the at least one open relationship forces the downlink signal to be transmitted only by the downlink loop, even if the downlink signal is partially turned on. state. The time division duplex control and protection device of claim 1, wherein the time division duplex wireless-fiber system has a downlink circuit and an uplink circuit for transmitting the downlink signal and the uplink signal respectively. When the at least one switch is activated in the second mode, the at least one open relationship selectively turns on the downlink loop or the uplink loop, even if the downlink signal and the uplink signal are in a fully conductive state. The time-division duplex control and protection device of claim 1, wherein the duty cycle delays the duty cycle of the downlink signal by a delay time and then delays the adjustment period. The digital downlink signal is superimposed with the original digital downlink signal. A method for time division duplex control and protection, which is applicable to a remote antenna unit in a time division duplex wireless-fiber system, the remote antenna unit transmits a downlink signal and receives an uplink signal, The method for time division duplex control and protection includes: receiving the downlink signal in the time division duplex wireless-fiber system, and the downlink signal has a duty cycle; and a start signal determining circuit determines whether the downlink signal transmission has been Starting, calculating the working period of the downlink signal, and comparing the working period of the downlink signal by a preset reference working period; when the comparison to the working period does not match the reference working period, Controlling at least one switch of the remote antenna unit to operate in a first mode; and when the comparison to the duty cycle coincides with the reference duty cycle, adjusting the duty cycle of the downlink signal, and adjusting The downlink signal controls the at least one switch in the remote antenna unit to perform in a second mode move. The method of time division duplex control and protection according to claim 9, wherein if the downlink signal is to be determined to be started, the method is selected within a limited time of the working period of the downlink signal. The downlink signal, if the bit value taken during the limited time is 1, determines that the downlink signal transmission has started. The method of time-division duplex control and protection according to claim 9 is characterized in that when the at least one switch is activated in the first mode, the downlink signal and the uplink signal are completely non-conducting. The method of time division duplex control and protection according to claim 9 is characterized in that when the at least one switch is operated in the first mode, the downlink signal portion is turned on. The method of time division duplex control and protection according to claim 9 is characterized in that when the at least one switch is operated in the second mode, the downlink signal and the uplink signal are completely turned on. The method of time-division duplex control and protection according to claim 9, wherein when the working period of the downlink signal is to be adjusted, the downlink signal is delayed by a delay time, and then the downlink signal is delayed. Superimposed with the original downlink signal.