KR100187970B1 - Up counter for pcs base station - Google Patents

Abstract

The present invention improves the characteristics and greatly reduces the size of the high frequency module for transmitting a personal mobile communication base station by combining a single compound semiconductor (GaAs) field effect transistor (MESFET MMIC) and a peripheral passive circuit. The present invention relates to an upconverter for a personal mobile communication base station that can improve and reduce a failure rate.

A low noise amplifier, a first bandpass filter, a first transformer, an oscillator, a mixer, a second transformer, an up-amp, and a second bandpass filter, each component of which is a hybrid integrated circuit, a single module, a ceramic substrate The die-bonded directly onto the wire and connected via a wire is characterized in that it is possible to move the frequency signal directly without the need for a separate connector between each component.

Description

Upconverter for personal mobile communication base station

1 is a view showing the configuration of a conventional up-converter.

2 is a block diagram showing a configuration according to an embodiment of the present invention.

3 is a detailed circuit diagram according to the present invention.

4 is a characteristic table according to an embodiment of the present invention.

5 is a view showing a product to which the present invention is applied.

* Explanation of symbols for main parts of the drawings

10: low noise amplifier 11: MESFET

12: input blocking capacitor 13: input matching circuit

14: automatic bio resistance and condenser 15: feedback resistance and coil

16: output matching circuit 17: drain resistance

18: output blocking capacitor 19: shock coil

20: first band pass filter 30: the first transformer

40: oscillator 41: voltage controlled oscillator

42: differential amplifier 43: buffer amplifier

44: PLL amplifier 50: mixer

60: second transformer 70: up-amp

80: second band pass filter

The present invention relates to an up-converter (UP CONVERTER) used in the personal mobile communication base station transmitter.

Commonly used upconverters in personal mobile communication base stations are low noise amplifiers, low frequency bandpass filters, double balance mixers, voltage control oscillators, and voltage control oscillators. It consists of six individual modules, such as an RF AMPLIFIER.

At this time, the up-converter according to the prior art is made of a plurality of individual modules as shown in Figure 1, and each module is used to connect to the connector, because each is put in the case with the input and output SMA connector is connected In addition to the large connector losses of the contact resistance, the impedance matching is different, and most silicon active devices have a problem in that the characteristics are greatly affected.

In addition, due to the six modules in the configuration of the up-converter occupies a large area, there is a problem that takes a lot of cost and time to repair the failure.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and its object is to combine a single compound semiconductor (GaAs) field effect transistor (MESFET MMIC) and a peripheral passive circuit into a single unit for high frequency transmission of a personal mobile communication base station. The purpose of the present invention is to provide an up-converter for a personal mobile communication base station that can improve the characteristics of the module and greatly reduce its size to improve the ease of use and reduce the failure rate.

According to a feature of the present invention for achieving the above object, a low noise amplifier for amplifying an input signal, a first band pass filter for passing only the frequency of the low frequency band of the signal amplified by the low noise amplifier, and the first band Two frequencies of 180 degrees out of phase by mixing the first transformer for distributing the frequency signal output from the pass filter into two signals, the oscillator for outputting the oscillation frequency, and the signals output from the first transformer and the oscillator. A mixer for outputting a signal, a second transformer for combining two frequency signals having a 180-degree phase difference output from the mixer into one, and an up-amplifier for amplifying only an upstream frequency signal among the frequency signals output from the second transformer; Of the frequency signals output from the up-amp, only the frequency signal of the desired band A second bandpass filter for passing; The low noise amplifier, the first bandpass filter, the first transformer, the oscillator, the mixer, the second transformer, the up-amp, and the second bandpass filter are hybrid integrated circuits, which are modularized and die-bonded directly on one ceramic substrate, By connecting through a strip pattern provides an up-converter for a personal mobile communication base station configured to directly move the frequency signal without the need for a separate connector between each component.

In addition, according to an additional feature of the present invention, the low noise amplifier comprises a GaAs MESFET having a noise figure of 1.5 dB, a gain of 15 dB, a third order interference point (IP3) of 33 dBm, and a size of 0.5 × 600 μm, and the mixer has a noise figure It consists of four GaAs MESFETs with 6.0dB, gain 6dB, 3rd order interference point (IP3) 26dBm and size 0.5 × 600µm.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

2 is a block diagram showing a configuration according to an embodiment of the present invention, Figure 3 is a detailed circuit diagram according to the present invention.

2 and 3, reference numeral 10 denotes a low noise amplifier, 20 denotes a first bandpass filter, 30 denotes a first transformer, 40 denotes an oscillator, 50 denotes a mixer, 60 denotes a second transformer, and 70 denotes an upward amplifier. , 80 represents a second band pass filter.

The low noise amplifier 10 includes an MESFET 11 for performing signal amplification, an input blocking capacitor 12 connected to the gate terminal of the MESFET 11, and a resistor and a coil connected to the gate terminal of the MESFET 11. It is connected between the input matching circuit 13, the automatic bio resistance and the capacitor 14 connected to the source terminal of the MESFET 11, and the gate terminal and the drain terminal of the MESFET 11 to widen the gain and widen the bandwidth. An output matching circuit 16 comprising a feedback resistor and a coil 15, a capacitor and a coil connected to the drain terminal of the MESFET 11, a drain resistor 17 connected to the drain terminal of the MESFET 11, and a MESFET ( An output blocking capacitor 18 connected to the drain terminal of 11) and a choke coil 19 connected between the supply power supply VDD and the drain resistor 17 to regulate the current of the drain and the source and to remove the high frequency component backflow. It is configured to include.

In the above, the MESFET 11 is a 600 μm GaAs MESFET, and each stage is connected to another device through a micro stripline.

In addition, the first band pass filter 20 includes a plurality of coils and a capacitor, and the first transformer 30 has a first-side coil having one end grounded for distributing the input signal into two having a 180 degree phase difference. It consists of a secondary coil that outputs a signal out of phase with the other.

In addition, the oscillator 40 includes a voltage controlled oscillator 41, a differential amplifier 42, a buffer amplifier 43, a PLL amplifier 44, and the like. In this case, the voltage controlled oscillator 41 includes a 150 μm GaAs MESFET, a transmission resonator, a tank circuit, and a varactor diode for wideband oscillation, depending on a voltage supplied to the varactor diode connected in parallel with the tank circuit. The oscillation frequency is changed. The differential amplifier 42 has two 40 μm GaAs MESFETs, which act as a buffer and produce two outputs 180 degrees out of phase. The buffer amplifier 43 is provided with two 150 μm GaAs MESFETs and produces an output of 15 dBm to the mixer 50.

The mixer 50 also consists of four bridge-shaped passive bisymmetric GaAs MESFETs with a size of 0.5 × 600 μm. At this time, the noise figure is 8.0dB, the gain is -8dB, and the third interference point (IP3) is 24dB. In operation, the gate power is applied very small, and it has -8dB insertion loss and 24dBm 3rd order interference point (IP3), so it passes the signal with less harmonics of INTERMODULATION AND CROSSMODULATION.

In addition, the second transformer 60 combines two signals having a phase difference of 180 degrees into one, a primary coil for receiving two signals, and one end of which is grounded to output a combined signal. It consists of the side coil.

In addition, the upward amplifier 70 is provided with a 600㎛ GaAs MESFET to amplify only the frequency by the sum of the oscillation frequency and the input signal of the signal passed through the mixer 50.

In addition, the second band pass filter 80 passes only the required frequency band using a microstrip three-pole interdigital filter or using a ceramic resonator filter.

Referring to the operation of the present invention configured as described above in detail as follows.

First, when a signal modulating the information of a voice and a data signal is input to the low noise amplifier 10 in a band of 70 MHz, the low noise amplifier 10 uses a low band of the wideband high frequency signals to increase a modulated signal to be transmitted. The gate balance circuit operates to reduce gain and compensate for the higher band. At this time, the coil value is made by using the input blocking capacitor 12 and the input matching circuit 13 to cut off the DC power supply to the microstrip 50k line of the ceramic substrate at the gate end of the MESFET 11. As a result, the low noise amplifier 200 operates to have a 3rd order interference point of 33 dBm while having an output of 18 dBm at 15 dB amplification and 1.5 dB noise figure.

Since the signal amplified by the low noise amplifier 10 includes many harmonics, only the required frequency band passes through the first band pass filter 20.

In order to supply to the mixer 50, since the phases must be separated into two signals having a 180 ° difference, the first transformer 30 is used. One of the two input terminals at the four terminals of the first transformer 30 is grounded 50 kHz, and when the signal of the first band pass filter 20 reaches the other terminal, the phase of the first output is 180 degrees. An output with < RTI ID = 0.0 > and a second output < / RTI > As a result, the two output signals are 1/2 in size compared to the input signals, and the phases are 180 degrees out of phase with each other.

On the other hand, when a predetermined oscillation frequency is provided to the differential amplifier 42 by the voltage controlled oscillator 41 of the oscillator 40, 2 in which the phase of the differential amplifier 42 is 180 degrees out of order to stabilize the oscillation frequency. After the two signals are made in one stage by the buffer amplifier 43, two signals having different phases of 15dBm output are supplied to the mixer 50. At this time, in order to stabilize the supplied oscillation frequency, a phase lock loop circuit (PLL) amplifier 44 is operated.

When the output signal of the first transformer 30 and the oscillation frequency of the oscillator 40 are input to the mixer 50 by the above operation, the even harmonics are canceled and mixed.

Two frequency signals having different phases among the mixed signals by the operation of the mixer 50 are combined into one signal in the second transformer 60.

On the other hand, the signal passed through the mixer 50 is the difference between the sum of the oscillation frequency and the input signal, of which the appropriate frequency is selected. First, in order to amplify only the sum frequency, the uplink amplifier 70 reduces the gain of the low band of the wideband high frequency signals, compensates the high band, and widens the gain flatness and the bandwidth. At this time, by using the automatic bias circuit, the negative voltage is automatically displayed on the gate by the drain and the source voltage by the resistor so that the compound semiconductor MESFET is operated even with a single voltage. As a result, the upstream amplifier 70 amplifies only the upstream frequency signal among the frequency signals output from the second transformer 60, so that an amplification of 10 dB, an output of 20 dBm, and a third interference point of 33 dBm are obtained.

Since many harmonics are generated in the signal amplified by the upstream amplifier 70, only the required frequency band is passed using the second bandpass filter 80.

4 is a characteristic table of an up-converter for a personal mobile communication base station according to an embodiment of the present invention as described above.

In the present invention, as shown in FIG. 5, the hybridization circuit as described above is placed in a case, connected to an input / output connector, and then operated by supplying a single power source. In order to mass-produce the functions of each of the above functions, a compound semiconductor made of a single microwave integrated circuit (MMIC) was used, and a matching line and a wire bonding pad were directly mounted on the integrated circuit and the alumina (ceramic) substrate. Connect the ceramic microstrip line and peripheral circuit.

In addition, low frequency amplifiers, voltage controlled oscillators, buffer amplifiers, mixers, low noise amplifiers, etc. have been greatly reduced in volume by using compound semiconductors. Sensitive passive devices are surface mounted on a ceramic substrate. At the same time, the compound semiconductor chip was attached on the integrated ceramic substrate, wire-bonded, and then epoxy-molded thereon to easily dissipate heat.

As described above, the upconverter for a personal mobile communication base station according to the present invention makes the module performing a plurality of functions into one module, thereby miniaturizing it compared to the prior art, and a separate connector is provided for each functional block unit. Since it is not necessary, there is an effect of performing thermally and electrically stable operation.

Claims (3)

A low noise amplifier for amplifying an input signal, a first band pass filter for passing only a frequency of a low frequency band among the signals amplified by the low noise amplifier, and a second signal for dividing a frequency signal output from the first band pass filter into two signals; A transformer and an oscillator for outputting two oscillation frequencies, a mixer for outputting two frequency signals by mixing the signals output from the first transformer and the oscillator, and combining the two frequency signals output from the mixer into one A second transformer, an up-amplifier for amplifying only an upstream frequency signal among the frequency signals output from the second transformer, and a second bandpass filter for passing only a frequency signal of a desired band among the frequency signals output from the up-amplifier Become; The low noise amplifier, the first bandpass filter, the first transformer, the oscillator, the mixer, the second transformer, the up-amp, and the second bandpass filter are hybrid integrated circuits, which are monomodulated, die-bonded directly on one ceramic substrate, and Up-converter for a personal mobile communication base station, characterized in that configured to enable the direct movement of the frequency signal without the need for a separate connector between each component. The personal mobile communication of claim 1, wherein the low noise amplifier, the first band pass filter, the first transformer, the oscillator, the mixer, the second transformer, the up amplifier, and the second band pass filter use a single power supply. Upconverter for base station. The low noise amplifier of claim 1, wherein the low noise amplifier comprises a GaAs MESFET having a noise figure of 1.5 dB, a gain of 15 dB, a third order interference point (IP3) of 33 dBm, and a size of 0.5 × 600 µm, and the mixer has a noise figure of 8.9 dB and a gain of 8.0. An upconverter for a personal mobile communication base station comprising four GaAs MESFETs having a dB, a third order interference point (IP3) of 24 dBm, and a size of 0.5 × 600 µm.