KR20080102518A - Triplexer - Google Patents

Abstract

A triplexer for producing a triplexer by minimum using passive devices is provided to improve the performance of attenuation and insertion loss between bands and minimize the influence of each band. A diplexer 1 connects to the other end of an antenna and separates CDMA band, GPS and PCS band. A diplexer 2 connects to the diplexer 1 and separates the GPS band and the PCS band. A triplexer consists of a bandpass filter of the GPS band. A parallel resonator is parallel connected to a capacitor and an inductor in case that the diplexer 1 separates the CDMA band, GPS and PCS band.

Description

Triplexer {Triplexer}

1 and 2 are block diagrams schematically showing components of a triplexer of a mobile communication terminal implemented by a conventional technology.

3 and 4 are circuit block diagrams showing the components of the triplexer circuit of the tri-mode terminal according to the present invention.

5 is a graph showing separation characteristics in each frequency band in the circuits of FIGS. 3 and 4;

6 is a conceptual diagram of manufacturing a passive triplexer using a general passive element.

7 is a conceptual diagram of a passive triplexer manufactured using a passive element embedded in a multilayer ceramic and organic packaging substrate.

The present invention relates to a triplexer circuit of a tri-mode terminal, and particularly, in a tri-mode terminal that simultaneously processes various modes such as CDMA, GPS, and PCS, insertion loss and isolation by combining several passive elements without using a single filter. The present invention relates to a triplexer circuit of a tri-mode terminal that effectively separates signals between frequency bands by improving characteristics.

The conventional dual band terminal has a diplexer capable of receiving two different frequencies of 1900 MHz band (PCS) and 800 MHz band (CDMA) through a single antenna. Recently, a dual band terminal has a GPS (Global Position) In addition to the system function, a triple-band system that can handle three frequency bands (PCS: 1850 to 1990 MHz, GPS: 1570 to 1580 MHz, and CDMA: 824 to 894 MHz) is used.

1 and 2 are block diagrams illustrating a configuration of a triple band mobile communication device implemented by a conventional technology.

Referring to FIG. 1, a conventional triple band mobile communication terminal includes an active switch, a CDMA signal processor, a PCS signal processor, a GPS signal processor, and a controller. The active switch is an antenna that performs a function of a triplexer. Separately receive / transmit the CDMA / PCS band signal or GPS signal received by

In this case, the antenna uses two antennas that selectively receive signals of different frequency bands, respectively. That is, the dual-band antenna is implemented to be received by tuning the frequency of the CDMA and PCS band, and the GPS antenna is implemented to tune and receive the frequency of the GPS band, it is shown as one antenna for convenience.

In addition, according to Figure 2, the triplex according to the prior art comprises a low pass filter, a high pass filter, a band pass filter, the low pass filter is a signal of the CDMA band by separating the signal, and the high pass The pass filter separates and processes the signal in the PCS band, and the bandpass filter separates the signal in the GPS band.

However, the conventional triplexer according to FIG. 1 implements all functions by forming an active switch corresponding to the triplexer in the form of a single chip, and according to the insertion loss caused by the high frequency in the wireless environment, There are various problems such as an increase in ripple in a pass band, difficulty in obtaining a required value of attenuation between each conducting band and another band. In addition, since the triplex according to FIG. 2 requires a lot of passive elements in order to improve the separation characteristics of the low pass / band / high pass filters from other bands, there is a difficulty in terms of the size and manufacturing cost of the triplex. .

In addition, in the case of the triplexer for simultaneously processing various modes such as CDMA, GPS, PCS as described above, these days are almost implemented as a chip, but as the number of modes to be implemented in the terminal increases, the frequency interval between modes This closeness makes it difficult to fabricate a single filter for filtering several signals simultaneously. Moreover, in the case of GPS and PCS, the frequency spacing is about 300 MHz, which makes it difficult to manufacture a diplexer and a triplexer for signal separation.

According to the present invention, a triplexer used in a terminal adopting a tri-band quad mode, which processes various modes such as CDMA, GPS, and PCS, is configured as a passive circuit combining several inductors and capacitors. The length between the transmission and reception paths can be shortened, and the triple that can reduce the influence of power lines that can occur especially when using an active switch, improve the insertion loss and attenuation characteristics between each band, and minimize the influence between the bands. The purpose is to provide a lexer.

Another object of the present invention is to minimize the number of passive elements, and to suppress the leakage current between each frequency band as much as possible, each frequency band signal is separated and maintained as a stable signal without mutual interference, miniaturized to be suitable for mounting in a mobile communication terminal To provide a triplexer. In addition, the passive triplexer products are integrated into the packaging substrate to achieve miniaturization, low cost, and thinness.

The present invention is to provide a triplexer circuit for separating the three frequency bands by combining only the GPS band pass filter and passive elements, it can be implemented as a multi-layer frequency separation circuit utilizing the circuit according to the present invention.

Hereinafter, a triplexer according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

3 is a circuit block diagram showing the components of a triplexer according to an embodiment of the present invention, Figure 4 is a circuit diagram showing the configuration of a triplexer circuit according to the present invention.

3, a triplex according to the present invention is provided in an RF communication module including an antenna and a plurality of signal processing units, and separates a first signal from a signal received from the antenna and transmits the first signal to the first signal processing unit. Diplexer; A diplexer for separating a third signal from a signal received from the diplexer and transmitting the third signal to a third signal processor; And a band pass filter for transmitting a second signal among the signals received from the diplexer to a second signal processor.

In addition, the band pass filter of the triplexer according to the present invention is characterized in that it is provided with a saw (SAW) or bow (BAW) filter.

According to FIG. 3, first, the antenna Ant converts power high frequency energy of a transmitter into radio wave energy at the time of transmission and radiates it into space, and receives radio wave energy of space and converts it into electric power at the time of reception, and supplies it to each receiver circuit.

Accordingly, the signal received through the antenna (Ant) is a CDMA frequency band (824MHz ~ 894MHz), GPS frequency band (1570 ~ 1580MHz), GPSS frequency band by the GPS bandpass filter through the triplexer circuit of the present invention It is separated into (1850MHz ~ 1990MHz).

Referring to FIG. 4, the present invention provides a first resonator, one end of which is connected to an antenna, a second resonator, which is connected to the other end of the first resonator, and a first resonator connected to the antenna in parallel with the first resonator. A die composed of a diplexer 1 comprising a first high pass filter, a third resonator connected to the diplexer 1, and a first low pass filter connected to the diplexer 1 in parallel with the third resonator; And a GPS filter unit connected to the flexure 2 and the first low pass filter.

The CDMA band frequency is separated through the first and second resonators, and the PCS band frequency is separated through the first high pass filter and the third resonator, and the first high pass filter and the first low pass filter; The GPS band frequency is separated through the GPS filter unit.

The first resonator serves as band rejection to a resonator in which a capacitor and an inductor are connected in parallel, and the second resonator includes a capacitor connected at one end to an output terminal of the first resonator and the other end of the capacitor. The resonator composed of this grounded inductor serves as band rejection. That is, the first and second resonators may selectively output only the CDMA band frequency by rejecting the GPS band frequency and the PCS band frequency from the signal received through the antenna.

The first high pass filter serves to select a high pass frequency as a high pass filter including a capacitor connected to an antenna at one end and an inductor connected to the other end of the capacitor and grounded at the other end. That is, the first high pass filter selectively outputs a band frequency including the PCS band frequency and the GPS band frequency in the signal received through the antenna.

The first and second resonators and the first high pass filter constitute a diplexer 1 connected to one end of the antenna.

The third resonator part serves as band rejection by a resonator including a capacitor connected to the other end of the first high pass filter, an inductor connected to the other end of the capacitor, and a capacitor connected to the other end of the inductor and grounded at the other end thereof. do. That is, the GPS band frequency is rejected from the signal received through the first high pass filter to selectively output only the PCS band frequency.

The first low pass filter may include an inductor connected to the other end of the first high pass filter and a capacitor connected to the other end of the inductor and the other end connected to the ground. Is an optional output.

The third resonator and the first low pass filter form a diplexer 2 that separates and outputs the GPS band frequency and the PCS band frequency.

To do this, select C1 = 1.6pF, C2 = 2.7pF, C3 = 2.7pF, C4 = 1.8pF, C5 = 1.1pF, C6 = 1.1pF in the circuit of Figure 4, L1 = 4.5nH, L2 = 2.4nH, L3 = 4.3nH, L4 = 9.4nH, L5 = 5.4nH to implement a triplexer.

At this time, the three bands are divided into a 25MHz band of each transmission and reception in the CDMA band, a 60MHz band of each transmission and reception in the PCS band, and a frequency band of 10MHz transmission and reception in the center (1575.42MHz) band of the GPS.

5 is a graph showing the results of experiments of the characteristics of the triplexer circuit according to the present invention, Figure 5 is a graph showing the insertion loss, return loss, attenuation characteristics for each frequency band to be.

Referring to the graph of FIG. 5, the insertion loss of the CDMA band in the triplex circuit of the present invention is -0.4 (dB), which is not significantly different from other diplexers, and includes a GPS bandpass filter. Insertion loss in one GPS band is -0.9 (dB), ensuring maximum performance by the filter, and insertion loss in PCS band is -0.3 ~ -0.7 (dB), which is higher than other bands but very hot. It is a good level, and the return loss in the low frequency band and the high frequency band is much higher than -15 (dB), and the attenuation also shows sufficient margin in all frequency bands.

6 and 7 are cross-sectional views of a triplexer constructed using a passive device according to an embodiment of the present invention.

FIG. 6 is constructed by mounting a copper circuit board using an inductor and a capacitor, which are discrete passive elements. In this case, the band pass filter of the GPS band is configured by using a saw (SAW) or beam (BAW) filter.

In addition, Figure 7 is a passive element inductor and capacitor embedded in a multilayer ceramic, organic packaging substrate, the band pass filter of the GPS band using a saw (SAW) or beam (BAW) mounted on the substrate after wire bonding or flip chip Implement by bonding.

According to the triplexer according to the present invention, since the triplexer can be manufactured using the minimum passive element, it can be directly applied to SOP technology or LTCC multilayer circuit using discrete passive element, copper foil laminated substrate or organic material. As a result, it is possible to manufacture at low cost, to realize miniaturization by optimizing the space utilization of the circuit board, to improve insertion loss and attenuation characteristics between each band, and to minimize the influence between the bands.

Claims (7)

Diplexer 1, which connects to the other end of the antenna and separates the CDMA band and GPS and PCS bands, and Diplexer 2, which connects to the other end of the diplexer 1 and separates the GPS and PCS bands, and a band pass filter of the GPS band Triplexer consisting of. The method of claim 1, wherein the diplexer 1 separating the CDMA band and the GPS and PCS bands includes a low pass filter and a capacitor including a parallel resonator in which a capacitor and an inductor are connected in parallel, and a series resonator in which the capacitor and the inductor are connected in series. Diplexer with highpass filter composed of inductors. [3] The diplexer 2 according to claim 2, wherein the diplexer 2 which is attached to the other end of the diplexer 1 and separates the GPS band and the PCS band comprises a low pass filter composed of an inductor and a capacitor, and a high pass filter composed of a capacitor and a series resonator. Diplexer. The triplexer of claim 1, wherein the bandpass filter of the GPS band is a SAW or BAW filter. The triplexer of claim 1, wherein the same circuit structure proposed by the present invention is implemented using a discrete passive element. The triplexer of claim 1, wherein the same circuit structure proposed by the present invention is implemented by embedding an inductor and a capacitor in a low temperature co-fired ceramic laminate. The triplexer of claim 1, wherein the same circuit structure proposed by the present invention is implemented by embedding an inductor and a capacitor in an organic substrate or a copper laminated substrate.

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