KR200204374Y1 - Apparatus for base station oscillation unit in wireless local loop - Google Patents

Abstract

The present invention adds a duplex circuit and a phase correction inductor-condenser circuit to a phase locked loop (PLL) used for radio frequency oscillation in a base station system of a wireless subscriber network (WLL). In order to provide an oscillation device for use, the present invention, the reference oscillator for oscillating a radio signal having a constant frequency; A plurality of phase-locked loops for phase-locking the radio signal oscillated by the reference oscillator at a specific frequency; A switching unit which selectively switches and transmits radio signals which are respectively phase-locked in the plurality of phase-locked loops; It is composed of a phase correction circuit for correcting the phase of the radio signal output from the switching unit, it is possible to transmit a stable signal even in the event of a failure of the system power supply unit or voltage control oscillation unit by the dual phase synchronization loop and phase correction circuit Since a plurality of phase-locked loops and a phase correction circuit operate in synchronization with one reference oscillator, it is possible to prevent a call degradation by preventing a phenomenon in which phase noise occurs due to a phase collision effect.

Description

Oscillator for base station of wireless subscriber network {Apparatus for base station oscillation unit in wireless local loop}

The present invention relates to an oscillation device of a radio frequency, and in particular, a redundant circuit and a phase correction inductor in a phased local loop (PLL) used for radio frequency oscillation in a base station system of a wireless local loop (WLL). The present invention relates to an oscillating device for a base station of a wireless subscriber network, which is suitable for adding a capacitor circuit (LC Tank) to improve the stability of the base station system.

In general, a base station system of a wireless subscriber network uses an oscillator to generate a radio frequency signal, and outputs the radio frequency generated by such an oscillator by synchronizing with the terminal frequency of a subscriber through a phase synchronization loop.

When the oscillated radio frequency is received by the subscriber station, wireless communication between the subscriber station and the base station is enabled.

Hereinafter, the oscillation apparatus for the base station of the wireless subscriber network according to the prior art.

First, Figure 1 is a block diagram of a base station oscillator of a wireless subscriber network according to the prior art.

As shown in FIG. 1, a conventional oscillator for a base station includes: a reference oscillator 11 for oscillating a radio signal having a specific frequency; A first divider 12 for dividing and outputting a radio signal oscillated by the reference oscillator 11; A phase comparator 13 for outputting phase difference data by comparing a phase of a radio signal divided by the first divider 12 and a radio signal input from the second divider 16; A loop filter 14 for generating a voltage signal by filtering phase difference data compared and output by the phase comparator 13; A voltage controlled oscillator (VCO) 15 for oscillating and outputting a wireless signal according to the voltage signal output from the loop filter unit 14; When the wireless signal outputted through the voltage controlled oscillator 15 is looped back and input, the second signal divider 16 divides the wireless signal and outputs it to the phase comparator 13.

Referring to the operation of the device according to such a configuration as follows.

When the oscillator provided in the base station system oscillates a radio signal and transmits the radio signal to the subscriber station, conventionally, one phase synchronization loop is used to adjust the phase synchronization of the radio frequency oscillated by the base station.

First, when a 10 MHz radio signal is oscillated by the reference oscillator 11, the first divider 12 divides the oscillated frequency signal and outputs the generated frequency signal to the phase comparator 13. The wireless signal output from the voltage controlled oscillator 15 is looped back, divided by the second divider 16, and then input to the phase comparator 13. At this time, the radio signal divided and output from the second divider 16 has a frequency of 10 MHz.

Then, the phase comparator 13 detects the phase difference between the radio signal looped back by the second division unit 16 and the radio signal divided by the first division unit 12 and outputs the phase difference to the loop filter unit 14. do. The loop filter unit 14 receives the phase difference data, removes the noise frequency, converts the noise frequency into a DC voltage, and outputs the converted voltage to the voltage controlled oscillator 15.

Therefore, when the radio signal is set to a specific frequency in the loop filter unit 14, a constant DC voltage is output to the voltage controlled oscillator unit 15. The voltage controlled oscillator 15 controlled according to the DC voltage output from the loop filter 14 generates and outputs a radio signal having a specific frequency.

As described above, the conventional base station oscillator generates phase difference data by comparing a phase of a radio signal oscillated by a reference oscillator and a radio signal oscillated by a voltage controlled oscillator with a phase comparator, and generates a voltage controlled oscillator using the phase difference data. By controlling the operation of generating a radio signal, the frequency of the radio signal transmitted from the base station can be synchronized to a specific frequency.

However, the above-described conventional oscillator for a base station of a wireless subscriber network uses a single phase-locked loop to phase-synchronize a radio signal oscillated to an outgoing radio signal. There was a problem in that there is a problem that does not have a countermeasure when a failure occurs and the frequency does not occur.

Therefore, the present invention is proposed to solve the conventional problems as described above, and an object of the present invention is a phase-locked loop (Phased Local) used for radio frequency oscillation in a base station system of a wireless local loop (WLL). The present invention provides an oscillator for a base station of a wireless subscriber network that improves the stability of a base station system by adding a redundant circuit and a phase correction inductor-capacitor circuit to a loop and a PLL.

In order to achieve the above object, an oscillator for a base station of a wireless subscriber network according to the present invention includes a reference oscillator for oscillating a radio signal having a predetermined frequency; A plurality of phase-locked loops for phase-locking the radio signal oscillated by the reference oscillator at a specific frequency; A switching unit which selectively switches and transmits radio signals which are respectively phase-locked in the plurality of phase-locked loops; The technical configuration is characterized by consisting of a phase correction circuit for correcting the phase of the radio signal output from the switching unit.

1 is a block diagram of an oscillation apparatus for a base station of a wireless subscriber network according to the prior art;

2 is a block diagram of an oscillator for a base station of a wireless subscriber network according to an embodiment of the present invention;

3 is a detailed block diagram of the phase locked loop of FIG.

Explanation of symbols on the main parts of the drawings

20: reference oscillator 30, 40: phase locked loop

50: switching unit 60: phase correction circuit

Hereinafter, the configuration and operation of the present invention according to an embodiment according to the technical idea of the base station oscillator of the wireless subscriber network according to the present invention as described above are as follows.

First, FIG. 2 is a block diagram of an oscillator for a base station of a wireless subscriber network according to an embodiment of the present invention, and FIG. 3 is a detailed block diagram of a phase locked loop in FIG.

As shown in FIG. 2, the oscillator for the base station according to the present invention includes: a reference oscillator 20 for oscillating a radio signal having a predetermined frequency; A plurality of phase-locked loops 30 and 40 for phase-locking the radio signal oscillated by the reference oscillator 20 at a specific frequency; A switching unit (50) for selectively switching and transmitting a radio signal output by phase synchronization in each of the plurality of phase synchronization loops (30) (40); It is composed of a phase correction circuit 60 for correcting the phase of the radio signal output from the switching unit 50.

As shown in FIG. 3, the plurality of phase-locked loops 30 includes: a first divider 31 for dividing and outputting a radio signal oscillated by the reference oscillator 20; A phase comparator 32 for outputting phase difference data by comparing a phase of a radio signal divided by the first divider 31 and a radio signal input from the second divider 35; A loop filter unit 33 for generating a voltage signal by filtering phase difference data compared and output by the phase comparison unit 32; A voltage controlled oscillator 34 for oscillating and outputting a wireless signal according to the voltage signal output from the loop filter unit 33; When the wireless signal outputted through the voltage controlled oscillator 34 is looped back and input, the second signal divider 35 divides the wireless signal and outputs it to the phase comparator 32.

Referring to the operation of the device according to such a configuration as follows.

The present invention duplicates and stabilizes a phase-locked loop of an oscillator used to generate a radio signal at a base station of a wireless subscriber network. That is, when the plurality of phase-locked loops 30 and 40 are used, and the reference oscillator 20 generates and outputs a radio signal having a constant frequency, the radio-signal is first and second phase-locked loops ( 30) 40.

The operations of the first and second phase-locked loops 30 and 40 that receive the radio signals of a predetermined frequency, respectively, oscillated by the reference oscillator 20 are the same as in the prior art. That is, in the case of the first phase-locked loop 30 for processing the oscillated radio signal, the first divider 31, the phase comparator 32, the loop filter 33, the voltage controlled oscillator 34, and the first The operation of the two frequency divider 35 is the same as that of the conventional phase-locked loop.

The first phase lock loop 30 and the second phase lock loop 40 have the same configuration, and perform the same operation. That is, the phase synchronization loop is doubled.

The radio signals output from the first and second phase lock loops 30 and 40 are selectively transmitted by the switching unit 50. That is, instead of simultaneously transmitting signals output from the two phase synchronization loops 30 and 40, only signals output from a specific phase synchronization loop are transmitted according to a control signal input from an external controller or the like.

Therefore, when a specific phase lock loop occurs in the two phase lock loops 30 and 40 and the voltage controlled oscillator does not operate so that the wireless signal is not output, a control signal specifying a fault lock phase lock loop is generated. It is input to the switching unit 50.

At this time, when the switching unit 50 performs the switching of the phase synchronization loop that operates normally from the specific phase synchronization loop malfunctioning, the phase correction circuit 60 to compensate for the output switching of the radio signal according to the interval of switching time It will be provided.

The phase correction circuit 60 generates a frequency stored in a circuit LC tank composed of an inductor-condenser when the radio signal output from the plurality of phase-locked loops 30 and 40 is switched. Therefore, it is possible to prevent the switching of the transmission signal generated during the output switching of the wireless signal, and to perform the transmission of the wireless signal stably despite the temporary switching of the wireless signal.

In order to perform this function, the phase correction circuit 60 stores a stable radio signal transmitted in a state where radio signal transmission is stably performed, and then outputs a stored radio signal when a failure occurs as described above. As such, the phase correction circuit 60 can transmit a radio signal in a state where a normal radio signal cannot be transmitted in an emergency, thereby preventing the transmission of the radio signal.

As such, the present invention processes a radio signal oscillated at one reference oscillator using a redundant phase synchronization loop, and switches a radio signal output from another phase synchronization loop that operates normally when a specific phase synchronization loop fails. When the transmission of the radio signal is switched according to the switching operation, the radio signal of the stable frequency stored in the phase correction circuit can be transmitted.

While the preferred embodiment of the present invention has been described above, the present invention may use various changes, modifications, and equivalents. It is clear that the present invention can be applied in the same manner by appropriately modifying the above embodiments. Therefore, the above description does not limit the scope of the present invention defined by the limits of the following utility model registration claims.

As described above, the base station oscillator of the wireless subscriber network according to the present invention uses a redundant phase synchronization loop and a phase correction circuit, so that even when a failure occurs in the system power supply unit or voltage controlled oscillator unit, transmission of the radio signal is switched. It prevents the signal transmission and enables stable signal transmission, thereby improving the call quality.

In addition, since a plurality of phase-locked loops and a phase correction circuit operate in synchronization with one reference oscillator, a phase noise can be prevented from occurring due to a phase collision effect, thereby preventing call degradation. Will have an effect.

Claims (2)

A reference oscillator for oscillating a radio signal having a constant frequency; A plurality of phase-locked loops for phase-locking the radio signal oscillated by the reference oscillator at a specific frequency; A switching unit which selectively switches and transmits radio signals which are respectively phase-locked in the plurality of phase-locked loops; An oscillator for a base station of a wireless subscriber network, characterized in that consisting of a phase correction circuit for correcting the phase of the radio signal output from the switching unit. The method of claim 1, wherein the phase-locked loop, A first divider for dividing and outputting a radio signal oscillated by the reference oscillator; A phase comparator configured to compare phases of the radio signal divided by the first divider and the radio signal input from the second divider to output phase difference data; A loop filter unit for generating a voltage signal by filtering phase difference data compared and output by the phase comparison unit; A voltage controlled oscillator for oscillating and outputting a wireless signal according to the voltage signal output from the loop filter; And a second divider for dividing a radio signal and outputting the radio signal to the phase comparator when the wireless signal outputted through the voltage controlled oscillator is looped back and inputted thereto.