CN1642028A - Front-end module for multi-frequency multi-mode wireless network system - Google Patents

Abstract

The invention discloses a front-end module for a multi-frequency multi-mode wireless network system, which comprises a diversity change-over switch, two wave band separation components, a plurality of band-pass filters, a plurality of low-pass filters and a plurality of unbalanced-to-balanced converters, wherein the number of the band-pass filters, the number of the low-pass filters and the number of the unbalanced-to-balanced converters are the same as the number of the wave bands which can be carried by a radio-frequency signal. In addition, all band separating components are connected with the diversity changeover switch, all band-pass filters are connected with one band separating component, all low-pass filters are connected with the other band separating component, and the unbalanced-to-balanced converter is connected with the band-pass filters in a one-to-one mode.

Description

Front-end module for multi-frequency multi-mode wireless network system

technical field

The present invention mainly relates to a front-end module, in particular to a front-end module for a multi-band and multi-mode wireless network system.

Background technique

There are two main classifications of wireless network technology, one is to use radio waves as the carrier of data transmission, and the other is to use light waves such as infrared (Infrared) and laser (Laser) as the carrier of data transmission.

As far as the use of radio waves as a carrier for data transmission can be divided into two development directions, one is used in short-distance (10 meters), low power (100mW) and low-cost Bluetooth technology, and the other is used in IEEE802.11 technology for office wireless transmission (bandwidth up to 54Mbps, and use distance up to about 100 meters).

Since 1997, the standard specifications of wireless network systems have been expanded from IEEE802.11 to IEEE802.11b/g/a, which means that the demand for multi-frequency and multi-mode has become a necessary development trend. On the other hand, a general wireless network system is composed of three parts: front-end module (front-end module), baseband processor (baseband processor, defined as PHY) and media access controller (Media Access Controller; MAC). The front-end module usually contains a large number of passive components such as capacitors, inductors, resistors, filters, and impedance converters. In order to meet the goals of low cost, small size, and low power consumption, these components must be modularized. And the miniaturized types are integrated to reduce the number of independent components.

The present invention proposes a front-end module for a wireless network system, which simultaneously meets the requirements of multi-frequency and multi-mode as well as the requirements of modularization and miniaturization.

Contents of the invention

In order to meet the requirements of multi-frequency, multi-mode and miniaturization of wireless network system applications in wireless communication systems other than mobile phones, the present invention proposes a front-end module for multi-frequency and multi-mode wireless networks. This front-end module adopts Laminated low temperature co-fired ceramics (Low Temperature CofiredCeramic; LTCC) method of production.

A front-end module for a multi-frequency multi-mode wireless network system according to an embodiment of the present invention includes two band separation components, a diversity switch, a plurality of bandpass filters, a plurality of unbalanced to balanced converters and a plurality of Second low pass filter. The number of band-pass filters, the number of unbalanced-to-balanced converters, and the number of low-pass filters are all the same as the number of bands that can be carried by a radio frequency signal.

In addition, each band separation component includes at least a high-pass filter and a first low-pass filter, which are responsible for separating the wireless bands that can be carried when the wireless network system receives radio frequency signals. The diversity switching switch connects any band separation component to any antenna. The bandpass filter is connected to one band-splitting component, the low-pass filter is connected to the other band-separating component, and the unbalanced-to-balun converter is connected to the bandpass filter one-to-one.

On the other hand, the band separation component, band-pass filter, unbalanced-to-balanced converter, and low-pass filter of the present invention are formed in a plurality of low-temperature co-fired ceramic substrates in a patterned manner, and the diversity switch is formed on the surface Adhesive technology is installed on the surface of the low temperature co-fired ceramic substrate.

The advantages of the present invention are as follows: first, it has the characteristics of multi-frequency and multi-mode to increase applicability. Second, the front-end module has the advantages of small size, good circuit heat dissipation, low cost and high reliability. Third, the design and production are highly matched, reducing production time.

Description of drawings

FIG. 1 is a block diagram showing a front-end module for a multi-frequency multi-mode wireless network system according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing a front-end module for a multi-frequency multi-mode wireless network system according to a second embodiment of the present invention.

FIG. 3 is a perspective view showing the configuration of the front-end module for the multi-frequency multi-mode wireless network system of the present invention on the low temperature co-fired ceramic substrate.

FIG. 4A is a schematic diagram showing the arrangement of the inductor of the front-end module for the multi-frequency multi-mode wireless network system on the low-temperature co-fired ceramic substrate of the present invention.

FIG. 4B is a schematic diagram showing the arrangement of the capacitors of the front-end module for the multi-frequency multi-mode wireless network system on the low-temperature co-fired ceramic substrate of the present invention.

Among them, the component symbols in the accompanying drawings are explained as follows:

1, 2 front-end module

10a, 10b, 20a, 20b antenna

11, 21 Diversity switch

12a, 12b duplexer

22a, 22b multiplexer

121a, 121b, 221a, 221b high pass filter

122a, 122b, 222a, 222b low pass filter

13a, 13b, 23a, 23b, 23c bandpass filter

15a, 15b, 25a, 25b, 25c Unbalanced to Balun

14a, 14b, 24a, 24b, 24c low pass filter

3～integrated circuit module

31～Low temperature co-fired ceramic substrate

311～Low temperature co-fired ceramic substrate surface layer

41, 51～conductive layer

42, 52～Metal vias

Detailed ways

The configuration components inside the front-end module used in the multi-frequency multi-mode wireless network system of the present invention and their relationship with signal reception and transmission will be described below with reference to the corresponding drawings.

Referring to Fig. 1, the front-end module 1 for the multi-frequency multi-mode wireless network system of the first embodiment of the present invention has at least one diversity switch (diversity switch) 11, two duplexers (diplexer) 12a and 12b, Two band pass filters (band pass filter) 13a and 13b, two low pass filters (low pass filter) 14a and 14b, two unbalanced to balanced converters (balun) 15a and 15b. The number of band-pass filters, the number of low-pass filters, and the number of unbalanced-to-balanced converters are all the same as the number of bands that can be carried by a radio frequency signal. In addition, the front end of the front-end module 1 is connected with two external antennas 10a and 10b, and the rear end has receiving ends RX11, RX12, RX21, RX22 and transmitting ends TX1, TX2 connected to the wireless network system.

In this embodiment, the diversity switch 11 will switch the duplexer 12a or 12b inside the front-end module 1 after the entire wireless network system automatically selects an antenna with the best signal reception condition based on the signal reception condition of the antenna 10a or antenna 10b Connect to a selected antenna.

These duplexers 12a and 12b have at least one high-pass filter 121a, 121b and one low-pass filter 122a, 122b inside as band separation components. In other words, the duplexer 12a is responsible for converting the available wireless bands f ₁ -f ₂ and f ₃ -f ₄ when the wireless network system receives radio frequency signals, such as the well-known ISM (Industrial, Science, Medical) public frequency band-2.4 ~2.5GHz and 5.15~5.85GHz are separated so that the radio frequency signals carried in different wireless bands can be distinguished. For example, the low-pass filter 122a of the duplexer 12a can only pass frequencies less than or equal to _f2 , and the high-pass filter 121a of the duplexer 12a can only pass frequencies greater than or equal to _f3 . The duplexer 12b is responsible for allowing radio frequency signals carried in different wireless bands to be transmitted separately when the wireless network system transmits radio frequency signals.

In addition, band-pass filters 13a and 13b are connected to the back end of duplexer 12a, and these band-pass filters 13a and 13b are respectively responsible for separating the non-wireless bands after the wireless bands f1 _{- f2} and _f3 - _f4 are separated. The signals of f ₁ ~ f ₂ and f ₃ ~ f ₄ are filtered out. The back ends of the bandpass filters 13a and 13b are also connected one-to-one with unbalanced-to-balanced converters 15a and 15b, through which the unbalanced-to-balanced converters 15a and 15b can be respectively mounted on the bands f ₁ to f ₂ and f The radio frequency signals from ₃ to f ₄ are converted into two radio frequency signals with a phase difference of 180 degrees, and are respectively received by the receiving ends RX11, RX12, RX21 and RX22 of the wireless network system.

The back end of the duplexer 12b is connected with low-pass filters 14a and 14b. When the wireless network system sends the radio frequency signal to be transmitted to the front-end module 1 through the receiving terminals TX1 and TX2, the low-pass filters 14a and 14b only allow the The radio frequency signals of the bands f ₁ -f ₂ and f ₃ -f ₄ are passed, and unnecessary signals generated in the wireless network system are filtered out. These unnecessary signals generated in the wireless network system include high frequency signals f ₁₁ ~ f ₂₁ , f ₃₁ ~ f ₄₁ and some Noise. Next, the radio frequency signals carried in the bands f ₁ -f ₂ and f ₃ -f ₄ are respectively transmitted through the duplexer 12b.

Referring to Fig. 2, the front-end module 2 for the multi-frequency multi-mode wireless network system in the second embodiment of the present invention has at least a diversity switch 21, two multiplexers (multi-plexer) 22a and 22b, a plurality of Band-pass filters 23a, 23b, 23c..., multiple low-pass filters 24a, 24b, 24c..., multiple unbalanced-to-balanced converters 25a, 25b, 25c.... The number of band-pass filters, the number of low-pass filters, and the number of unbalanced-to-balanced converters are all the same as the number of bands that can be carried by a radio frequency signal. In addition, the front end of the front end module 2 is connected with two external antennas 20a and 20b, and the rear end has receiving ends RX11, RX12, RX21, RX22, RX31, RX32... and transmitting ends TX1, TX2, TX3....

In this embodiment, the diversity switching switch 21 automatically selects an antenna with the best signal receiving condition based on the signal receiving condition of the antenna 20a or the antenna 20b in the entire wireless network system, and switches the multiplexer 22a or the multiplexer 22a inside the front-end module 2 22b is connected to a selected antenna.

These multiplexers 22a and 22b have at least one high-pass filter 221a, 221b and one low-pass filter 222a, 222b inside, and sometimes may also have a band-pass filter (not shown) as a band separation component. In other words, the multiplexer 22a is responsible for separating the wireless bands f ₁ ~ f ₂ , f ₃ ~ f ₄ , f ₅ ~ f ₆ ... that can be carried by the wireless network system when receiving radio frequency signals, so that the The radio frequency signals in different bands can be distinguished, and the multiplexer 22b is responsible for making the radio frequency signals carried in different radio bands f ₁ ~ f ₂ , f ₃ ~ f ₄ , f ₅ ~ f ₆ .. . The radio frequency signal can be sent out respectively.

In addition, bandpass filters 23a, 23b, 23c... are connected to the back end _of the multiplexer 22a, and these bandpass filters _23a , _23b , _23c ... _{, f 5 ˜f 6 . _ _} The back ends of the bandpass filters 23a, 23b, 23c... are also connected one-to-one with unbalanced-to-balanced converters 25a, 25b, 25c..., through these unbalanced-to-balanced converters 25a, 25b, 25c. ..It can convert the radio frequency signals carried on the bands f ₁ ~ f ₂ , f ₃ ~ f ₄ , f ₅ ~ f ₆ ... into two radio frequency signals with a phase difference of 180 degrees, which are respectively transmitted by the wireless network system The receiving end RX11, RX12, RX21, RX22, RX31, RX32... receive.

The back end of the multiplexer 22b is connected with low-pass filters 24a, 24b, 24c..., these low-pass filters 24a, 24b, 24c... pass through the receiving ends TX1, TX2, TX3... When the radio frequency signal to be transmitted is sent to the front-end module 2, only the radio frequency signals carried in the bands f ₁ ~ f ₂ , f ₃ ~ f ₄ , f ₅ ~ f ₆ ... pass through, while the radio frequency signals generated in the wireless network system Unnecessary signal filtering. These unnecessary signals generated in the wireless network system include the high-frequency signals f ₁₁ ~ f ₂₁ , f ₃₁ ~ f ₄₁ , f ₅₁ ~ f ₆₁ generated after the radio frequency signal to be transmitted is amplified by a power amplifier. ..and some noise. Next, the radio frequency signals carried in the bands f ₁ -f ₂ , f ₃ -f ₄ , f ₅ -f ₆ . . . are respectively transmitted out through the multiplexer 22b.

In each of the above-mentioned embodiments, the diversity switches 11 and 21 respectively include at least one gallium arsenide (GaAs) switch and its associated passive components (such as capacitors with large capacitance and resistors), and the duplex 12a and 12b, multiplexers 22a and 22b, bandpass filters 13a, 13b, 23a, 23b, 23c..., unbalanced to balanced converters 15a, 15b, 25a, 25b, 25c..., low-pass The filters 14a, 14b, 24a, 24b, 24c... all include LC circuits composed of capacitors and inductors.

Please refer to FIG. 3 , the front-end modules 1 and 2 for the multi-frequency multi-mode wireless network system of the present invention are both made of a multi-layer low temperature co-fired ceramic (Low Temperature Cofired Ceramic; LTCC) substrate 31 to form an integrated circuit module 3 . Here, each layer of low-temperature co-fired ceramic substrate 31 is mainly composed of many ceramic dielectric materials and contains many conductive layers therein.

In detail, due to the partial components of the front-end modules 1 and 2 for the multi-frequency multi-mode wireless network system of the present invention, including duplexers 12a and 12b, multiplexers 22a and 22b, bandpass filters 13a, 13b, 23a, 23b, 23c..., unbalanced to balanced converters 15a, 15b, 25a, 25b, 25c..., low-pass filters 14a, 14b, 24a, 24b, 24c... are composed of capacitors and inductors Therefore, the inventors formed these capacitors and inductors inside the low-temperature co-fired ceramic substrate 31 of each layer by patterning. In addition, the inventors surface mounted the gallium arsenide (GaAs) switches of the diversity switches 11 and 21 and their auxiliary passive components (such as capacitors with large capacitance and resistors) and other active components such as semiconductor components of ICs. Surface mounting technology (SMT) is mounted on the uppermost layer of the integrated circuit module 3 , that is, the surface layer 311 of the uppermost layer of low temperature co-fired ceramic substrate 31 .

As shown in FIG. 4A , in the manufacturing process, the above-mentioned inductors are formed on the conductive layer 41 inside the low temperature co-fired ceramic substrate 31 of each layer in a strip patterned manner to become strip electrodes, and between the conductive layers 41 There is a dielectric layer (not shown), and the conductive layers 41 are connected by metal via holes (via holes) 42, therefore, the connection pattern of the inductor in the multilayer low temperature co-fired ceramic substrate 31 is a spiral type. On the other hand, as shown in FIG. 4B, these capacitors are formed on the conductive layer 51 inside each layer of low-temperature co-fired ceramic substrate 31 in a block-shaped pattern to form a block-shaped electrode, and there is a dielectric between each conductive layer 51. layers (not shown), and the conductive layers 51 are connected by metal vias 52 , therefore, the connection type of the capacitor inside the multilayer low temperature co-fired ceramic substrate 31 is an overlapping type.

In addition, the LC circuit inside the low-temperature co-fired ceramic substrate 31 of each layer below the surface layer 311 of the low-temperature co-fired ceramic substrate is diversity switching on the surface layer 311 of the low-temperature co-fired ceramic substrate through the metal vias 42 and 52 between the above-mentioned conductive layers. Gallium arsenide (GaAs) switches of the switches 11 and 21 are electrically connected with their auxiliary passive components and active components such as ICs.

Part of the components of the front-end modules 1 and 2 used in the multi-frequency multi-mode wireless network system of the present invention can effectively reduce the volume occupied by these components after they are embedded in a multilayer ceramic substrate in a patterned manner and integrated into an integrated circuit. , so in addition to meeting the requirements of multi-frequency and multi-mode, it can also meet the requirements of modularization and miniaturization of the wireless network system.

To sum up, the present invention has been described in detail through the above-mentioned embodiments and variations. However, it should be understood by those skilled in the art that all the embodiments of the present invention are merely illustrative rather than restrictive. Other variations and modifications of the front-end module of the frequency multi-mode wireless network system are covered by the present invention. Accordingly, the invention is defined by the appended claims.

Claims (11)

1. A front-end module for a multi-frequency multi-mode wireless network system, which is connected with two antennas, and the front-end module includes: Two band separation components, each of which includes at least a high-pass filter and a first low-pass filter; a diversity switch, connecting any one of the band separation components to any one of the antennas; a plurality of bandpass filters, the number of which is the same as the number of bands that can be carried by a radio frequency signal, and connected to one of the band separation components; a plurality of unbalanced to balanced converters, the number of which is the same as the number of bands that can be carried by the radio frequency signal and connected one-to-one with the bandpass filter; and A plurality of second low-pass filters, the number of which is the same as the number of bands that the radio frequency signal can carry, is connected to the other one of the band separation components. 2. The front-end module for a multi-frequency multi-mode wireless network system as claimed in claim 1, wherein the band separation component is a multiplexer. 3. The front-end module for a multi-frequency multi-mode wireless network system as claimed in claim 1, wherein the band separation component, the bandpass filter, the unbalanced to balanced converter and the second low The pass filter is formed in a plurality of low temperature co-fired ceramic substrates in a patterned manner, and the diversity switching switch is arranged on a surface layer of the low temperature co-fired ceramic substrates. 4. The front-end module for multi-frequency multi-mode wireless network system as claimed in claim 3, wherein said low temperature co-fired ceramic substrate has a plurality of conductive layers and a plurality of dielectric layers, and between said conductive layers Metal vias are provided. 5. The front-end module for a multi-frequency multi-mode wireless network system as claimed in claim 4, wherein the band separation component, the bandpass filter, the unbalanced to balanced converter and the second low The pass filter respectively includes a plurality of capacitors and a plurality of inductors, which are patterned and formed on the conductive layer. 6 . The front-end module for a multi-frequency multi-mode wireless network system as claimed in claim 5 , wherein the pattern of the capacitor is block-shaped and the pattern of the inductor is strip-shaped. 7. The front-end module for a multi-frequency multi-mode wireless network system as claimed in claim 5, wherein the capacitor and the inductor are connected to the low temperature co-fired ceramic substrate through a metal via hole between the conductive layers of the surface layer. 8. The front-end module for a multi-frequency multi-mode wireless network system as claimed in claim 3, wherein the diversity switch comprises a GaAs switch and its associated passive components. 9. The front-end module for a multi-frequency multi-mode wireless network system as claimed in claim 8, wherein the gallium arsenide switch and its auxiliary passive components are mounted on the surface layer of the low temperature co-fired ceramic substrate by surface mount technology . 10. The front-end module for a multi-frequency multi-mode wireless network system as claimed in claim 3, wherein the surface layer has an IC component. 11. The front-end module for multi-frequency multi-mode wireless network system as claimed in claim 1, wherein each of the unbalanced to balanced converters is connected with two receiving ends, and each of the second low-pass filters Connect with a transmission terminal.

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