KR20000045007A - Power amplifier having transmission line coupler with external connecting structure - Google Patents

Abstract

PURPOSE: A power amplifier is provided to implement high-outputting power and high-outputting addition gain, by designing an amplifying terminal of the power amplifier as a parallel structure to maximumly amplify dispersed power in each amplifier, and by connecting a transmission line coupler having an external connecting structure composed of a transmission line and a resistor to an outputting terminal of the power amplifier. CONSTITUTION: A power amplifier comprises many amplifiers(2,3,4,5) and an output power coupler(1). The amplifiers amplify distributed input signals, respectively in parallel, and amplify power required by dispersing the power. The output power coupler is composed of many input terminal couplers and an output terminal coupler. The input terminal couplers correspondingly couple the input signals amplified in the amplifiers, respectively. The output terminal coupler couples each coupling signal outputted from the input terminal couplers, and outputs the coupling signals. The output power coupler comprises first to second input terminal couplers(1-10,1-20) and an output terminal coupler(1-30). The first to the second input terminal couplers couple the amplified signals inputted from the input terminals. The output terminal coupler couples again the two coupling signals outputted from the first/the second input terminal couplers, and outputs the two coupling signals.

Description

Power amplifier with transmission line coupler external connection structure and layout method

The present invention provides a mobile communication terminal for a next generation mobile communication system (International Mobile Telecommunication-2000; "IMT-2000") or Future Public Land Mobile Telecommunication System (hereinafter, "FPLMTS"). The present invention relates to a power amplifier which is an output stage of a wireless transmitter. Particularly, a structure in which a coupler is connected outside the power amplifier so as to maximize the output power and output gain efficiency of the high output. It relates to a power amplifier having a and a layout method thereof.

In general, the power amplifier of the mobile communication terminal RF transmitter should have the characteristics of reducing the battery consumption of the terminal and amplifying the input RF signal with high amplification gain efficiency and output power. In addition, in order to be applied to a mobile phone, it should basically have characteristics of small size, light weight, and low cost. On the other hand, the power amplifier of the RF transmitter, which is used to amplify the transmitted RF signal, can be manufactured in a single chip with small size and light weight by monolithic microwave integrated circuits (MMIC). It may be desirable to implement the circuitry either within the MMIC 1-chip power amplifier or externally.

In addition, since the power amplifier consumes the highest power among components constituting the RF transceiver, the amplification efficiency of the power amplifier directly affects the time when the terminal can be used with a single charge. However, since output power and amplification gain efficiency are different from each other, the output stage must be designed to satisfy both of these parameter characteristics, and to obtain an output signal having high output power and high output gain efficiency. There is a demand for a coupler capable of coupling in a multi-stage (parallel structure) method.

Disclosure of Invention The present invention has been made to solve the above-described problems, and an object thereof is to provide a power amplifier such that the amplified output signal of a power amplifier having a parallel structure has high output gain and high output gain efficiency. .

In addition, another object of the present invention is a transmission line having a high output gain and high output gain efficiency by designing a coupler of a connection structure for coupling the amplified output signal of a power amplifier having a parallel structure from the outside as a transmission line and a lumped resistor It is an object of the present invention to provide a power amplifier having a coupler external connection structure and a layout method thereof.

1 is a block diagram of an embodiment of a power amplifier having a transmission line coupler external connection structure according to the present invention.

FIG. 2 is an embodiment layout of a circuit for coupling output power using a transmission line and a resistor to the external coupler of FIG.

3A is an input / output characteristic diagram of an amplifier coupled to a lumped element optimized for the external coupler of FIG. 1.

3B is an input / output characteristic diagram of an amplifier coupled with a resistor and an ideal transmission line to the external coupler of FIG. 1;

4 is a layout of an embodiment of a circuit for output power coupling using a lumped element to the external coupler of FIG.

5 is an embodiment layout of a circuit for coupling output power using transmission lines and resistors ideal for the external coupler of FIG.

Explanation of symbols on the main parts of the drawings

1: external coupler

2, 3, 4, 5: Amplifiers for distributed input power

1-10, 1-20, 1-30: each input power combiner

V12 to V18: Via hole ground

40: DC input voltage connection pad

C11 to C13: capacitor

L11: Inductor

L12: Inductor

R11, R12, R13, R _L : resistance

ST11, ST12, ST23: transmission line

TML12; Engineered grid " "Shaped transmission line

TML13; Designed Transmission line

TML11; Designed " "Shaped transmission line

TML11 to TML23; Engineered transmission lines

WTML11 to WTML23: Designed transmission line and transmission line for combiner of resistance structure

SLTL11 to SLTL23: ideal transmission line and transmission line for combiner of resistance structure

In order to achieve the above object, a power amplifier having a transmission line coupler external connection structure according to the present invention comprises: a plurality of amplifying means for distributing and amplifying desired power by amplifying a plurality of distributed input signals in parallel; And a plurality of input stage combining means for correspondingly combining the plurality of signals amplified by the plurality of amplifying means, respectively, and an output stage combining means for combining all of the combined signals outputted from the plurality of input stage combining means. It characterized in that it comprises a; output power coupling means configured to.

In the above configuration, the output power combining means includes first and second input stage combining means for combining the amplified signals input to the plurality of input stages, and two combined signals outputted from the first and second input stage combining means. Characterized in that it is composed of output stage coupling means for outputting by combining.

The first and second input end coupling means may include a first resistor connected between the first input port and the second input port, respectively; A first transmission line connected in parallel with the resistor with respect to the first input port; A second transmission line connected in parallel with the resistor with respect to the second input port; And a third transmission line connected to the first and second transmission line output side common contacts.

The output stage coupling means may include a second resistor connected between an output side of the first input port and the second input port; A fourth transmission line connected in parallel with the second resistor with respect to the output side of the first input port; A fifth transmission line connected in parallel with the second resistor with respect to the output side of the second input port; And a sixth transmission line having an input side connected to the fourth and fifth transmission line output side common contacts.

In addition, the first and second input end coupling means, respectively, the first capacitor connected between the first input port and the ground; A second capacitor connected between the second input port and ground; A first resistor connected between the first input port and the first input port; And a second inductor connected in parallel with the first resistor with respect to the second input port.

The output stage coupling means may include a second capacitor and a second resistor grounded between the common contact and the output port of the first and second inductor output sides of the first and second input stage coupling means, respectively. .

The power amplifier layout method having a transmission line coupler external connection structure according to the present invention for achieving the above another object, by amplifying a plurality of input signals by a plurality of amplifying means in parallel to distribute and amplify the desired power, A plurality of input stage coupling means correspondingly combines a plurality of signals amplified by the plurality of amplification means, respectively, and output stage coupling means combines and outputs each combined signal outputted from the plurality of input stage coupling means. It is characterized by.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings so that those skilled in the art may easily implement the technical idea of the present invention. do. In the drawings, the same reference numerals are used for the same components as in the prior art.

First, in order to satisfy the output of the terminal for the IMT-2000, a preferred embodiment of the present invention configures an amplifier in which four field effect transistors (FETs) are connected in parallel, and these outputs are configured. It is designed to obtain high output power and high output gain efficiency by connecting transmission line coupler designed using transmission line and lumped element (resistor), which is the structure of coupler that connects power from outside.

For example, as a preferable example of the present invention, a FET (library element of GEC-Marconi, UK) having a gate width of 900 μm may be used, and the present invention focuses on an output power port of a power amplifier using such a FET. A transmission line coupler was connected externally and the output power and output gain efficiency were measured. As a result, a power amplifier with an output of about 570 mW and an efficiency of about 41% was obtained. This results in an improvement of about 31, 87 mW, 3.1, and 9.3% in output power and amplification gain, respectively, compared to the output stage using an ideal transmission line coupler and lumped element coupler (see Table 1 below). > Reference)

Meanwhile, the above power amplifier should be applied to the terminal for IMT-2000, so the design and manufacturing cost and volume should be minimized. Accordingly, in the present invention, the output stage of the power amplifier can be implemented by MMIC (Monolithic Microwave Integrated Circuits), but the circuit for combining the output signal of the parallel output port is much larger than a general chip device, and implemented as an MMIC chip. Since it is not suitable for the following, the coupler of the external connection structure was comprised using the transmission line and the lump element.

1 is a diagram illustrating an embodiment of a power amplifier having an external connection structure of a transmission line coupler according to the present invention.

As shown in FIG. 1, a power amplifier having a coupler connection structure according to the present invention receives an output signal of a driving amplifier which is a front end (not shown: which is connected to the front end of a power amplifier in a terminal). For example, the first and second amplifiers 2 and 3, the third and fourth amplifiers 4 and 5, which provide optimized amplified signals using an FET having a gate width of 900 μm, And an output power transmission line combiner 1 for coupling the input terminals of the combiners connected to the outside of the output stages of the fourth amplifiers 2, 3, 4, and 5, respectively, to couple the output signals amplified by the respective amplifiers. .

As shown in FIG. 1, the configuration of the entire power amplifier, which is an external connection structure of the coupler, has a structure in which an output signal from the power amplifiers 2, 3, 4, and 5 is received.

Since the output signal is amplified by the amplifiers 2, 3, 4, and 5 having a parallel structure and included in the MMIC on-chip, RF (Radio Frequency) signals input through the respective input ports are Amplified power is output from an output terminal of each of the amplifiers 2, 3, 4, and 5 to an output port having a parallel structure.

FIG. 2 is a layout of a circuit for coupling output power using a transmission line and a resistor to the external coupler of FIG. 1.

As shown in FIG. 2, a signal input terminal (Input port 2 to Input port 5) connected through an input pad (RF input port) to receive an output signal of the amplifiers 2, 3, 4, and 5 applied from the outside. The first and second input stage coupling units 1-10 and 1-20 for coupling the amplified signals input to the two input terminals Input port2, Input port3, Input port4 and Input port5, respectively, It is provided with an output stage coupling unit (1-30) for combining and outputting the combined two output signals again. Here, the term coupling portion will be used interchangeably with the term coupling means.

The first input coupler 1-10 includes a resistor R12 connected between an input port 1 and an input port 2, transmission lines WTML11 and WTML12 connected in parallel with the resistor R12, and the transmission lines WTML11 and WTML12. Transmission line (WTML16) having an input side connected to a common contact point of two transmission line output sides consisting of transmission lines (WTML13 and WTML14) connected in parallel with the resistor (R12) and the same transmission lines (WTML15) as the two transmission lines (WTML13 and WTML14). And a transmission line WTML17 connected in series with the transmission line WTML16.

The second input end coupling part 1-20 has the same structure as the connection configured in the first input end coupling part 1-10.

The output stage coupling unit 1-30 connects the output terminal of the transmission line WTML17, which is the end of the first input terminal 1-10, and the output terminal of the transmission line WTML17, which is the end of the second input terminal 1-20, in parallel. A resistor R13, two transmission lines WTML18 connected in parallel with the resistor R13, and a transmission line WTML19 and a transmission line WTML20 connected in series to the ends of the two transmission lines WTML18. It consists of a transmission line WTML22 having an input side connected to a common contact of two transmission line output sides composed of the same transmission line WTML21 as the transmission lines WTML19 and WTML20, and a transmission line WTML23 connected in series with the transmission line WTML22. ) Is matched to the load resistance (R _L = 50 ohms) and used as the output port.

The combiner composed of the transmission line and the resistor according to the present embodiment is optimized for optimal load impedance, and serves to couple the output powers of the four amplifiers 2, 3, 4, and 5 shown in FIG.

On the other hand, the output stage coupler of the Wilkinson coupler structure composed of the transmission line and the resistor combines the output from each amplifier with a minimum loss (about 3 dB) while matching the output stage impedance. This structure and the value of the circuit elements improve the output power and output gain efficiency of the entire power amplifier, there is a loss of connecting the output connection external connection coupler, but the effect of improving the overall output power and output gain efficiency and In comparison, it can be said to be a negligible loss.

In addition, the RF signal output from each of the amplifier is input to the transmission line combiner (1) connected from the outside to be the final combined output power.

One embodiment of a transmission line coupler 1 connected to an output port of the input power amplifiers 2, 3, 4, and 5 of FIG. 1 from outside can be confirmed.

That is, as shown in the figure, the input power amplifier includes a resistor R11 for widening the bandwidth of the radio frequency (RF) and a field effect transistor (FET900) for amplifying the power of the RF signal for producing a desired output. ), An inductor L11 for feeding and supplying DC power to apply a voltage between the gate and the source of the field effect transistor, a cross for connecting an input port and the elements ( ), A microstrip line (TML11), an inductor (L12) for feeding and supplying a DC power supply to apply a voltage between the drain and the source of the field effect transistor, and a plurality of each provided between the input and output terminals of the elements Of ) And work ( A) shaped microstrip line (ST11) (ST12) is provided.

In the input power amplifiers 2, 3, 4, and 5 of FIG. 1, the power that one FET, which is an FET amplification block connected in parallel, can be output by a 1 dB compression point of the amplifier. Because of the limitations, power must be distributed and amplified when using the same power amplifier to produce the desired high output. 4, each amplifier has the same characteristic.

The RF input signal port of FIG. 1 is branched in three directions on a cross-shaped microstrip line TML21 through a straight transmission line. The voltage (Vgs) applied to the gate of the amplifying FET having a gate width of 900 μm is passed through the inductor L11 for DC power feeding and input stage matching through a connection pad (F20DCAP) used to supply DC power in the MMIC chip. Supplied. In addition, the resistor R11 serves to widen the bandwidth of the amplified RF frequency.

On the other hand, Vds supplied to the drain of the FET is supplied via the inductor L12 for DC power feeding and output stage matching.

3A is an input / output characteristic diagram of an amplifier coupled to a lumped element optimized for the external coupler of FIG. 1.

FIG. 3B is an input / output characteristic diagram of an amplifier coupled with an ideal transmission line and a resistor to the external coupler of FIG. 1.

FIG. 4 is a layout of a circuit for output power coupling using a lumped element to the external coupler of FIG. 1, wherein the output power combiner of the power amplifier of FIG. 1 is a lumped resistor R11, R13, R _L. ), And capacitors C11 to C13 and inductors L11 and L12.

As shown in the drawing, in the case of an output power combiner using a lumped element, the first and second input stage combiners 1-10, which combine the signals amplified by the power amplifiers input to the two input stages, respectively, 1-20) and an output stage combiner 1-30 which combines and outputs two combined signals outputted therefrom.

The first input coupler 1-10 includes a capacitor C11 connected between an input port 2 and a ground V13, a capacitor C12 connected between an input port 3 and a ground V14, the input port 2, and an input port 3. An inductor L11 connected in parallel with a resistor R11 connected therebetween, and an inductor L12 connected in parallel with the resistor R11 with respect to the input port 3.

The second input end coupling unit 1-20 is a structure for coupling an amplified input signal applied to the input port 4 and the input port 5, and has the same structure as the first input end coupling unit 1-10. .

The output stage coupling unit 1-30 is a capacitor (V15) grounded between a common contact and an output port of the output side of the inductors L11 to L12 of the first and second input stage coupling units 1-10 and 1-20. C11) and resistor R11.

FIG. 5 is a layout of an embodiment of a circuit for coupling output power using a transmission line and a resistor ideal for the external coupler of FIG. 1, and as shown in FIG. Do the same.

FIG. 5 is a circuit diagram illustrating an embodiment in which the output power combiner of FIG. 1 is configured by using an ideal transmission line and a resistor that is a lumped element.

As shown in the figure, an ideal transmission line combiner using transmission lines SLTL11 to SLTL23, resistors R12, R13, and R _L , which combines amplified signals inputted at two input terminals, respectively. (1-10, 1-20) and the output stage combiner (1-30) for combining and outputting the two combined signals output from the first and second input stage combiner (1-10, 1-20) again Equipped.

The first input coupling unit 1-10 is connected in parallel with a resistor R12 connected between the input port 2 and the input port 3 ( A parallel transmission line (SLTL11) and the U-shaped transmission line (SLTL11) ) Transmission line (SLTL12), above Connected in series with the output of the L-shaped transmission line (SLTL11, SLTL12) It consists of a transmission line SLTL13.

The second input end coupling unit 1-20 is a structure for coupling an amplified input signal applied to the input port 4 and the input port 5, and has the same structure as the first input end coupling unit 1-10. .

In addition, the first input terminal coupling unit 1-30 may include the resistor R13 and the output terminal of the first input terminal coupling unit 1-10 and the output terminal of the second input terminal coupling unit 1-20. Connected in parallel with the resistor R12 with respect to the output terminal of the first input coupling unit 1-10; ) Transmission line (SLTL14), the two Connected in series with the output terminal of the transmission line (SLTL14) ) Transmission line (SLTL23), and It consists of a resistor (R _L ) connected between the output side of the transmission line (SLTL14) and ground.

In FIG. 5, as in FIGS. 2 and 4, the input coupling units are arranged symmetrically, and the corresponding functional units have the same function.

5 illustrates an example in which an output stage coupler is configured using a lumped element, and the device values are optimized to obtain a desired output and efficiency. As a result, the output characteristics are similar to those implemented using a transmission line. I could get the value. On the other hand, Figure 1 is configured and exemplified by using an ideal transmission line, which shows poor characteristics compared to other cases.

The three output characteristics compared above, i) a coupler optimized with transmission line and resistance (see Figure 4), ii) a coupler optimized with lumped elements (see Figure 3c), iii) Table 1 shows the characteristics of an amplifier coupled with a resistor and a transmission line conceived in the present invention among the total power amplifiers combined by using a transmission line (see FIG. 5).

As described above, the coupler circuit of the present invention connecting a lossless coupler having an external connection structure can be utilized as an RF transmitter power amplifier for an IMT-2000 terminal, and the power of the RF transmitter of a wireless local area network (WLL) terminal. It can also be widely used as a key element of the amplifier output stage.

Although the foregoing has been described with respect to embodiments of the present invention, those skilled in the art will understand that various implementations are possible within the scope of the technical idea of the present invention. In addition, those skilled in the art will be capable of various modifications, changes, additions, and the like within the spirit and scope of the present invention, and such modifications and changes should be regarded as belonging to the following claims.

According to the present invention as described above, the output of the power amplifier implemented by the MMIC can be significantly larger than conventional commercial components, and the output amplifier not only improves the gain efficiency, but also designed the power amplifier amplification stage in a parallel structure. By amplifying the distributed power to the maximum in each amplifier, and connecting the transmission line combiner having an external connection structure consisting only of the transmission line and the resistance at the output terminal to the output terminal of the power amplifier, there is an effect that can realize high output power and high output gain gain efficiency.

Claims (9)

In the power amplifier, A plurality of amplifying means for distributing and amplifying a desired power by amplifying each of a plurality of distributed input signals in parallel; And And a plurality of input stage coupling means for correspondingly combining the plurality of signals amplified by the plurality of amplification means, respectively, and an output stage coupling means for combining all of the combined signals outputted from the plurality of input stage coupling means. Output power coupling means Power amplifier having a transmission line coupler external connection structure comprising a. The method of claim 1, The output power coupling means, First and second input stage coupling means for coupling the amplified signals input to the plurality of input stages; And Output stage combining means for combining and outputting two combined signals outputted from the first and second input stage combining means again Power amplifier having a transmission line coupler external connection structure comprising a. The method of claim 2, The first and second input end coupling means, respectively, A first resistor connected between the first input port and the second input port; A first transmission line connected in parallel with the resistor with respect to the first input port; A second transmission line connected in parallel with the resistor with respect to the second input port; And A third transmission line connected to the common contact at the output side of the first and second transmission lines Power amplifier having a transmission line coupler external connection structure comprising a. The method of claim 3, wherein The output stage coupling means, A second resistor connected between the output side of the first input port and the second input port; A fourth transmission line connected in parallel with the second resistor with respect to the output side of the first input port; A fifth transmission line connected in parallel with the second resistor with respect to the output side of the second input port; And A sixth transmission line having an input side coupled to the fourth and fifth transmission line output side common contacts; Power amplifier having a transmission line coupler external connection structure comprising a. The method of claim 2, The first and second input end coupling means, respectively, A first capacitor connected between the first input port and ground; A second capacitor connected between the second input port and ground; A first resistor connected between the first input port and the first input port; And First and second inductors connected in parallel with the first resistor to the second input port; Power amplifier having a transmission line coupler external connection structure comprising a. The method of claim 5, The output stage coupling means, A third capacitor and a second resistor grounded between the common contact and the output port of the first and second inductor output sides of the first and second input stage coupling means, respectively Power amplifier having a transmission line coupler external connection structure comprising a. The method of claim 2, The first and second input end coupling means, respectively, A first resistor connected between the first input port and the second input port; A first magnetic transmission line connected in parallel with the first resistor with respect to the first input port; A second magnetic (-) transmission line connected in parallel with the first resistor with respect to the second input port; A first memory device connected in series with the first zigzag transmission line ( ) Transmission line; A second memory device connected in series with the second zigzag transmission line ( ) Transmission line; A first date connected in series with the first memory type transmission line ) Transmission line; A second date connected in series with the second memory type transmission line ) Transmission line; And A third letter coupled to the contact portions of the first and second linear transmission lines ( ), Including the transmission line The output stage coupling means, A second resistor connected between an output end of the first input end coupling means and an output end of the second input end coupling means; A fourth letter connected in parallel with the second resistor with respect to the output terminal of the first stage coupling means ( ) Transmission line; A fifth letter connected in parallel with the second resistor with respect to the output terminal of the second stage coupling means ( ) Transmission line; A third memory device connected in series with the fourth U-shaped transmission line ( ) Transmission line; A fourth memory device connected in series with the fifth zigzag transmission line ( ) Transmission line; A third date connected in series with the third memory type transmission line ) Transmission line; A fourth date connected in series with the fourth memory type transmission line ) Transmission line; And A fifth letter coupled to a contact portion of the third and fourth linear transmission lines ( ) Transmission line; And Let's say the fifth Third resistor connected between the output side of the transmission line and ground Power amplifier having a transmission line coupler external connection structure comprising a. In the power amplifier layout method having a transmission line coupler external connection structure, By amplifying a plurality of input signals distributed in parallel by a plurality of amplification means, the desired power is distributed and amplified, A plurality of input stage coupling means respectively corresponding to the plurality of signals amplified by the plurality of amplification means, And a transmission line combiner external connection structure, characterized in that the output stage combining means combines and outputs each combined signal outputted from the plurality of input stage combining means. The method of claim 8, The output power coupling means, First and second input stage coupling means for coupling the amplified signals input to the plurality of input stages; And Output stage combining means for combining and outputting two combined signals outputted from the first and second input stage combining means again Power amplifier layout method having a transmission line coupler external connection structure, characterized in that consisting of.