CN-122001392-A - High frequency circuit

CN122001392ACN 122001392 ACN122001392 ACN 122001392ACN-122001392-A

Abstract

A high frequency circuit transmits and receives high frequency signals in a frequency band 28, a frequency band 28B and a frequency band 29 while suppressing the circuit scale. The high frequency circuit includes a first bandpass filter having a passband upstream of the frequency band 28 of LTE, a second bandpass filter having a passband downstream of the frequency band 28 of LTE, a third bandpass filter having a passband upstream of the frequency band 28B of LTE and downstream of the frequency band 29 of LTE, and a switch bank. The switch group includes a first terminal for electrically connecting an output terminal of the power amplifier and one end of the first band-pass filter, a second terminal for electrically connecting the other end of the first band-pass filter and a high-frequency signal input/output terminal, a third terminal for electrically connecting an input terminal of the low-noise amplifier and one end of the second band-pass filter, and a fourth terminal for electrically connecting the other end of the second band-pass filter and the high-frequency signal input/output terminal.

Inventors

Daiken Takeshi
Sen Hongsi

Assignees

株式会社村田制作所

Dates

Publication Date: 20260508
Application Date: 20251103
Priority Date: 20241106

Claims (8)

1. A high-frequency circuit is provided with a high-frequency signal input terminal, a high-frequency signal output terminal, and a high-frequency signal input/output terminal, and comprises: A power amplifier having an input terminal electrically connected to the high-frequency signal input terminal; A low noise amplifier having an output terminal electrically connected to the high frequency signal output terminal; a first band pass filter having a passband that is upstream of a frequency band 28 of long term evolution, LTE; A second bandpass filter having a passband downstream of the frequency band 28 of LTE; a third band pass filter having a passband of up-band 28B of LTE and down-band 29 of LTE, and The switch group is provided with a plurality of switches, The switch group includes: A first terminal for electrically connecting an output terminal of the power amplifier with one end of the first band-pass filter; A second terminal for electrically connecting the other end of the first band-pass filter with the high-frequency signal input/output terminal; A third terminal for electrically connecting between an input terminal of the low noise amplifier and one end of the second band pass filter; a fourth terminal for electrically connecting the other end of the second band-pass filter with the high-frequency signal input/output terminal; A fifth terminal for electrically connecting between an output terminal of the power amplifier and one end of the third band-pass filter; A sixth terminal for electrically connecting the other end of the third band-pass filter with the high-frequency signal input/output terminal, and And a seventh terminal for electrically connecting an input terminal of the low noise amplifier with one end of the third band pass filter.
2. The high-frequency circuit according to claim 1, wherein, And a fourth bandpass filter having a passband upstream of the frequency band 20 of LTE, The second band pass filter has a passband downstream of band 28 of LTE and downstream of band 20 of LTE, The switch group is used for electrically connecting the output terminal of the power amplifier with one end of the fourth band-pass filter, electrically connecting the other end of the fourth band-pass filter with the high-frequency signal input/output terminal, electrically connecting the input terminal of the low-noise amplifier with one end of the second band-pass filter, and electrically connecting the other end of the second band-pass filter with the high-frequency signal input/output terminal.
3. The high-frequency circuit according to claim 1, wherein, In the case of power level 2 i.e. the action of PC2, The switch group electrically connects the output terminal of the power amplifier with one end of the first band-pass filter, the other end of the first band-pass filter with the high-frequency signal input/output terminal, the input terminal of the low-noise amplifier with one end of the second band-pass filter, the other end of the second band-pass filter with the high-frequency signal input/output terminal, In the case of power level 3 i.e. the action of PC3, The switch group is used for electrically connecting the output terminal of the power amplifier with one end of the third band-pass filter, electrically connecting the other end of the third band-pass filter with the high-frequency signal input/output terminal, electrically connecting the input terminal of the low-noise amplifier with one end of the second band-pass filter, and electrically connecting the other end of the second band-pass filter with the high-frequency signal input/output terminal.
4. A high-frequency circuit according to claim 1 or 3, wherein, The switch group comprises a first switch, a second switch and a third switch, A first terminal of the first switch is electrically connected with an output terminal of the power amplifier, a second terminal of the first switch is electrically connected with a second terminal of the second switch, a third terminal of the first switch is electrically connected with one end of the first band-pass filter, a fourth terminal of the first switch is electrically connected with one end of the third band-pass filter, A first terminal of the second switch is electrically connected with an input terminal of the low noise amplifier, a second terminal of the second switch is electrically connected with a second terminal of the first switch, a third terminal of the second switch is electrically connected with one end of the second band-pass filter, The first terminal of the third switch is electrically connected with the other end of the first band-pass filter, the second terminal of the third switch is electrically connected with the other end of the second band-pass filter, the third terminal of the third switch is electrically connected with the other end of the third band-pass filter, and the fourth terminal of the third switch is electrically connected with the high-frequency signal input and output terminal.
5. The high-frequency circuit according to claim 2, wherein, The switch group comprises a first switch, a second switch and a third switch, A first terminal of the first switch is electrically connected with an output terminal of the power amplifier, a second terminal of the first switch is electrically connected with a second terminal of the second switch, a third terminal of the first switch is electrically connected with one end of the first band-pass filter, a fourth terminal of the first switch is electrically connected with one end of the third band-pass filter, a fifth terminal of the first switch is electrically connected with one end of the fourth band-pass filter, A first terminal of the second switch is electrically connected with an input terminal of the low noise amplifier, a second terminal of the second switch is electrically connected with a second terminal of the first switch, a third terminal of the second switch is electrically connected with one end of the second band-pass filter, The first terminal of the third switch is electrically connected with the other end of the first band-pass filter, the second terminal of the third switch is electrically connected with the other end of the second band-pass filter, the third terminal of the third switch is electrically connected with the other end of the third band-pass filter, the fourth terminal of the third switch is electrically connected with the high-frequency signal input and output terminal, and the fifth terminal of the third switch is electrically connected with the other end of the fourth band-pass filter.
6. The high-frequency circuit according to claim 4 or 5, wherein, In the case of transmitting and receiving a high frequency signal of the frequency band 28 of LTE, The first switch electrically connects the first terminal to the third terminal, The second switch electrically connects the first terminal to the third terminal, The third switch electrically connects the first terminal with the fourth terminal, and electrically connects the second terminal with the fourth terminal, In the case of transmitting and receiving the high frequency signal of the frequency band 28B of LTE, The first switch electrically connects the first terminal to the fourth terminal, The second switch electrically connects the first terminal to the third terminal, The third switch electrically connects the second terminal with the fourth terminal, and electrically connects the third terminal with the fourth terminal, In the case of receiving a high frequency signal of the frequency band 29 of LTE, The first switch electrically connects the second terminal to the fourth terminal, The second switch electrically connects the first terminal to the second terminal, The third switch electrically connects the third terminal to the fourth terminal.
7. The high-frequency circuit according to claim 5, wherein, In the case of transmitting and receiving a high frequency signal of the frequency band 20 of LTE, The first switch electrically connects the first terminal to the fifth terminal, The second switch electrically connects the first terminal to the third terminal, The third switch electrically connects the second terminal to the fourth terminal and electrically connects the fourth terminal to the fifth terminal.
8. The high-frequency circuit according to any one of claims 4 to 7, wherein, In the case of power level 2 i.e. the action of PC2, The first switch electrically connects the first terminal to the third terminal, The second switch electrically connects the first terminal to the third terminal, The third switch electrically connects the first terminal with the fourth terminal, and electrically connects the second terminal with the fourth terminal, In the case of power level 3 i.e. the action of PC3, The first switch electrically connects the first terminal to the fourth terminal, The second switch electrically connects the first terminal to the third terminal, The third switch electrically connects the second terminal to the fourth terminal and electrically connects the third terminal to the fourth terminal.

Description

High frequency circuit Technical Field The present disclosure relates to a high frequency circuit. Background Patent document 1 below describes a high-frequency circuit for transmitting and receiving high-frequency signals in a plurality of frequency bands. Prior art literature Patent literature Patent document 1 U.S. patent application publication No. 2013/0247422 Disclosure of Invention Problems to be solved by the invention Conventionally, a frequency band 28 of LTE (Long Term Evolution: long term evolution) is divided into a low-frequency band 28A and a high-frequency band 28B for use. With respect to the frequency of band 28, the upper behavior is 703MHz (megahertz) to the 45MHz width of 748MHz, and the lower behavior is 758MHz to the 45MHz width of 803 MHz. With respect to the frequency of band 28A, the upper behavior is 703MHz to 733MHz in 30MHz width, and the lower behavior is 758MHz to 788MHz in 30MHz width. With respect to the frequency of band 28B, the upper behavior is 718MHz to 748MHz in 30MHz width, and the lower behavior is 773MHz to 803MHz in 30MHz width. Hereinafter, in the present disclosure, the frequency band 28 is sometimes referred to as "B28" or "B28F". Band 28A is sometimes referred to as "B28A". Band 28B is sometimes referred to as "B28B". The uplink is sometimes referred to as "UL". The downlink is sometimes referred to as "DL". In recent years, there has been a demand from the market for communication in the frequency band of the frequency band 28 by using frequencies of 40MHz or more in the uplink and downlink, respectively. However, as described above, each of the frequency bands 28A and 28B has a width of only 30MHz in the uplink and downlink, respectively. Thus, a need arises to utilize the frequency band 28. In addition, frequencies of 470MHz to 710MHz are used for terrestrial digital television broadcasting according to countries (e.g., japan). Thus, in the case of using the band 28B, the specification of NS_17 is specified by 3GPP (registered trademark) (Third Generation Partnership Project: third generation partnership project). That is, in the case of using the frequency band 28B, it is necessary to suppress signals of frequencies of 470MHz to 710 MHz. The frequency band 29 is a downlink-only frequency band. The frequency band 29 has a frequency of 717MHz to 728MHz. That is, the frequency of band 29 is included in the frequency upstream of band 28. Hereinafter, in the present disclosure, the frequency band 29 is sometimes referred to as "B29". Thus, in the case where the high-frequency circuit transmits and receives the high-frequency signals of the frequency band 28, the frequency band 28B, and the frequency band 29, many filters and many switches are required. The present disclosure has been made in view of the above-described circumstances, and an object thereof is to transmit and receive high-frequency signals in the frequency band 28, the frequency band 28B, and the frequency band 29 while suppressing the circuit scale. Solution for solving the problem The high-frequency circuit according to one aspect of the present disclosure is a high-frequency circuit including a high-frequency signal input terminal, a high-frequency signal output terminal, and a high-frequency signal input/output terminal, and includes a power amplifier having an input terminal electrically connected to the high-frequency signal input terminal, a low-noise amplifier having an output terminal electrically connected to the high-frequency signal output terminal, a first band-pass filter having a passband of an LTE band 28 upstream of a long-term evolution band, a second band-pass filter having a passband of an LTE band 28 downstream of the band, a third band-pass filter having a passband of an LTE band 28B upstream of the band and a band 29 downstream of the LTE band, and a switch group having a first terminal for electrically connecting an output terminal of the power amplifier to one end of the first band-pass filter, a second terminal for electrically connecting the other end of the first band-pass filter to the high-frequency signal input terminal, a third terminal for electrically connecting an input terminal of the low-noise amplifier to one end of the second band-pass filter, a fourth terminal for connecting the other end of the second band-pass filter to the band-pass filter to one end of the second band-pass filter, a band-pass filter having a passband of the high-pass filter between the other end of the second band-pass filter and the first band-pass filter and the other end of the high-pass filter, and a third terminal for connecting the input terminal to the high-pass filter. Effects of the invention According to the present disclosure, it is possible to transmit and receive high-frequency signals of the frequency band 28, the frequency band 28B, and the frequency band 29 while suppressing the circuit scale. Drawings Fig. 1 is a diagram illustrating frequencies of frequency band 28 and