CN117896226A

CN117896226A - Signal processing method, signal processing device and communication equipment

Info

Publication number: CN117896226A
Application number: CN202211227753.7A
Authority: CN
Inventors: 杨永兴
Original assignee: ZTE Corp
Current assignee: ZTE Corp
Priority date: 2022-10-09
Filing date: 2022-10-09
Publication date: 2024-04-16
Also published as: WO2024078019A1

Abstract

The embodiment of the invention provides a signal processing method, a signal processing device and communication equipment, wherein the signal processing method is applied to the signal processing device and comprises the following steps: when receiving the multi-path carrier signals, acquiring multi-path frequency band information of the multi-path carrier signals; when the multi-channel frequency band information is matched with a preset interference frequency band, classifying the multi-channel carrier signals according to the interference frequency band to obtain a first type carrier signal and a second type carrier signal, wherein the first type carrier signal is at least two paths of carrier signals with signal frequency bands interfering with each other in the multi-channel carrier signals; filtering the first type carrier signals to obtain filtered signals; and generating a combined signal according to the filtering signal and the second type carrier signal, thereby realizing the integration of the transmission of the multi-path carrier signals, eliminating the interference influence of the carrier signals when the multi-path carrier signals are transmitted simultaneously, and improving the filtering performance of the signal processing device.

Description

Signal processing method, signal processing device and communication equipment

Technical Field

The present invention relates to the field of communications technologies, and in particular, to a signal processing method, a signal processing apparatus, and a communications device.

Background

Currently, a multi-carrier technology is used to convert a high-speed serial data stream into a multi-path low-speed parallel data stream, so that data can be transmitted between a radio frequency chip and an antenna through multiple paths of carrier signals at the same time, which requires that a radio frequency front-end device process multiple paths of carriers at the same time, and then a signal processing device, such as a radio frequency front-end device, is arranged between the radio frequency chip and the antenna to amplify and filter multiple carrier signals that are interacted with each other.

However, due to technical limitations, the architecture of the existing signal processing device is huge and complex, and it is difficult to eliminate interference existing between the multiple carrier signals during simultaneous transmission, so that the filtering performance of the signal processing device is seriously affected, and the working performance of the signal processing device in performing multiple transmission cannot meet the actual use requirements.

Disclosure of Invention

The embodiment of the invention mainly aims to provide a signal processing method, a signal processing device and communication equipment, which are used for integrating multi-path carrier signal transmission, eliminating interference influence of carrier signals during simultaneous transmission of the multi-path carrier signals and improving filtering performance of the signal processing device.

In a first aspect, an embodiment of the present invention provides a signal processing method, including:

when receiving the multi-path carrier signals, acquiring multi-path frequency band information of the multi-path carrier signals;

when the multi-channel frequency band information is matched with a preset interference frequency band, classifying the multi-channel carrier signals according to the interference frequency band to obtain a first type carrier signal and a second type carrier signal, wherein the first type carrier signal is at least two paths of carrier signals with signal frequency bands interfering with each other in the multi-channel carrier signals;

filtering the first type carrier signals to obtain filtered signals;

and generating a combined signal according to the filtered signal and the second carrier signal.

In some embodiments, filtering the first type carrier signal to obtain a filtered signal includes:

determining signal frequency band overlapping parts of at least two first-type carrier signals as interference frequency bands;

signals in an interference frequency band in at least one first type carrier signal are filtered.

In some embodiments, filtering signals in an interference frequency band from at least one first type of carrier signal includes:

determining a specific sub-frequency band matched with the interference frequency band;

signals in the corresponding specific sub-frequency band are filtered out.

In some embodiments, before determining the signal band overlapping portion of the at least two first type carrier signals as the interference band, the method further includes:

determining a target frequency band according to the multipath frequency band information;

and carrying out preset amplification processing on carrier signals in a target frequency band in the multi-channel carrier signals.

In some embodiments, generating a combined signal from the filtered signal and the second type carrier signal comprises:

respectively carrying out corresponding phase shifting treatment on the filtered signal and the second carrier signal so as to enable the phase difference between signals of any two frequency bands in the filtered signal and the second carrier signal to be in a preset target phase difference range;

and combining the phase-shifted filtered signal with the second carrier signal to obtain a combined signal.

In a second aspect, an embodiment of the present invention further provides a signal processing apparatus, including:

the information acquisition module is used for acquiring multi-channel frequency band information of the multi-channel carrier signals when receiving the multi-channel carrier signals;

the signal classification module is used for classifying the multi-channel carrier signals according to the interference frequency bands when the multi-channel frequency band information is matched with the preset interference frequency bands to obtain a first-type carrier signal and a second-type carrier signal, wherein the first-type carrier signal is at least two carrier signals with signal frequency bands interfering with each other in the multi-channel carrier signal;

The signal filtering module is used for filtering the first type carrier signals to obtain filtered signals;

and the signal combining module is used for generating a combined signal according to the filtered signal and the second carrier signal.

In some embodiments, the signal filtering module includes a multiplexer, where the multiplexer is provided with multiple filtering channels corresponding to multiple signal frequency bands respectively;

the signal filtering module performs filtering processing on the first type carrier signals to obtain filtered signals, and the method comprises the following steps:

and controlling at least one filtering channel corresponding to the interference frequency band to filter signals in the interference frequency band in the corresponding first carrier signals.

In some embodiments, the filtering channel is provided with a plurality of traps for filtering out different specific sub-band signals respectively and a gating switch for connecting with the plurality of traps;

the method for controlling the filtering channel of at least one corresponding interference frequency band to filter signals in the interference frequency band in the corresponding first carrier signals comprises the following steps:

in at least one filtering channel corresponding to the interference frequency band, determining a target trap matched with the corresponding specific sub-frequency band and the interference frequency band;

The target trap is controlled to work through the gating switch so that the target trap filters signals in a corresponding specific sub-frequency band.

In some embodiments, the signal filtering module further includes multiple amplifying channels respectively corresponding to the multiple signal frequency bands, and the amplifying channels are connected with the filtering channels corresponding to the signal frequency bands;

before determining the signal frequency band overlapping portion of the at least two first type carrier signals as the interference frequency band, the method further comprises:

and controlling an amplifying channel corresponding to the target frequency band to perform preset amplifying processing on the carrier signals in the target frequency band in the multi-channel carrier signals.

In some embodiments, the signal combining module includes a plurality of frequency bands and a plurality of phase shifters respectively corresponding to a plurality of signal frequency bands, generates a combined signal according to the filtered signal and the second carrier signal, and includes:

the phase shifters corresponding to the control signal frequency bands respectively perform corresponding phase shifting processing on the filtering signals and the second carrier signals so as to enable the phase difference between the filtering signals and the signals of any two frequency bands in the second carrier signals to be in a preset target phase difference range;

and controlling the multifrequesters to carry out combining processing on the filtered signals after the phase shift processing and the second carrier signals to obtain combined signals.

In some embodiments, the signal processing apparatus includes an integrally packaged matching circuit, a radio frequency power amplifier, a low noise amplifier, a multiplexing filter, a phase shifter, a switching unit, and a multi-frequency band.

In a third aspect, an embodiment of the present invention further provides a communication device, where the communication device includes a radio frequency communication device, a signal transceiver, and a signal processing device connected to the radio frequency communication device and the signal transceiver, where the signal processing device is configured to perform any one of the signal processing methods provided in the specification of the present application;

the radio frequency communication device is used for outputting multi-path carrier signals to the signal processing device, and the signal receiving and transmitting device is used for receiving the combined signals generated by the signal processing device; or (b)

The signal transceiver is used for outputting multi-path carrier signals to the signal processing device, and the radio frequency communication device is used for receiving the combined signals generated by the signal processing device.

In summary, an embodiment of the present invention provides a signal processing method, a signal processing device, and a communication device, where the signal processing method includes: when receiving a multi-channel carrier signal, acquiring multi-channel frequency band information of the multi-channel carrier signal, classifying the multi-channel carrier signal according to an interference frequency band when the multi-channel frequency band information is matched with a preset interference frequency band to obtain a first type carrier signal and a second type carrier signal, wherein the first type carrier signal is at least two paths of carrier signals with signal frequency bands interfering with each other in the multi-channel carrier signal, and then filtering the first type carrier signal to obtain a filtered signal; and generating a combined signal according to the filtering signal and the second type carrier signal, thereby realizing the integration of the transmission of the multi-path carrier signals, eliminating the interference influence of the carrier signals when the multi-path carrier signals are transmitted simultaneously, and improving the filtering performance of the signal processing device.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present application, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic flow chart of a signal processing method according to an embodiment of the present invention;

fig. 2 is a schematic block diagram of a signal processing apparatus according to an embodiment of the present invention;

fig. 3 is a schematic flow chart of filtering processing on a first type of filtering signal in a signal processing method according to an embodiment of the present invention;

fig. 4 is a schematic block diagram of a signal filtering module of a signal processing device according to an embodiment of the present invention;

fig. 5 is a schematic block diagram of another signal filtering module of the signal processing device according to the embodiment of the present invention;

fig. 6 is a schematic block diagram of a signal filtering module of a signal processing device according to an embodiment of the present invention;

fig. 7 is a schematic block diagram of a signal combining module of a signal processing device according to an embodiment of the present invention;

Fig. 8 is a schematic block diagram of a communication device according to an embodiment of the present invention.

Detailed Description

The following description of the embodiments of the present invention will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are some, but not all embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

The flow diagrams depicted in the figures are merely illustrative and not necessarily all of the elements and operations/steps are included or performed in the order described. For example, some operations/steps may be further divided, combined, or partially combined, so that the order of actual execution may be changed according to actual situations.

It is to be understood that the terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used in this specification and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

The signal processing method provided by the embodiment of the invention can be applied to a signal processing device, and the signal processing device is respectively connected with a radio frequency communication device and a signal receiving and transmitting device in a communication way, and is particularly used for amplifying and filtering signals transmitted from the radio frequency communication device to the signal receiving and transmitting device or from the signal receiving and transmitting device to the radio frequency communication device.

For convenience and cleanliness of description, the signal processing method provided by the application is executed by the signal processing device, but it should be understood that the signal processing method provided by the application is not limited to be applied to the signal processing device.

Some embodiments of the invention are described in detail below with reference to the accompanying drawings. The following embodiments and features of the embodiments may be combined with each other without conflict.

Referring to fig. 1, fig. 1 is a flow chart of a signal processing method according to an embodiment of the invention.

As shown in fig. 1, the signal processing method includes steps S101 to S104.

And step S101, when receiving the multi-path carrier signals, acquiring multi-path frequency band information of the multi-path carrier signals.

As shown in fig. 2, the signal processing method provided in the present application is specifically described by executing the signal processing device. The signal processing device 200 is communicatively connected to the radio frequency communication device 300 and the signal transceiver device 400, respectively, and the radio frequency communication device 300 is, for example, a radio frequency chip, and the signal transceiver device 400 is, for example, an antenna. It should be noted that, as will be clearly understood by those skilled in the art, the radio frequency communication device 300 includes, but is not limited to, a radio frequency chip, the signal transceiver 400 includes, but is not limited to, an antenna, and for convenience and brevity of description, the following embodiments take the radio frequency communication device 300 as the radio frequency chip and the signal transceiver 400 as an example.

In some embodiments, a radio frequency communication device, such as a radio frequency chip, outputs a signal to a signal transceiver, such as an antenna, through a signal processing device, and the signal transceiver transmits the signal to an external device, where the external device includes, but is not limited to, a communication base station and a mobile communication device that are communicatively connected to the signal transceiver. It should be understood that, in addition to the radio frequency communication device outputting a communication signal to the signal transceiving device through the signal processing device, in the case that the signal transceiving device receives an external signal output at an external device, the signal transceiving device may also output a communication signal to the radio frequency communication device through the signal processing device 200 to enable communication interaction between the radio frequency communication device and the signal transceiving device.

Specifically, the signal processing apparatus 200 includes a signal acquisition module 410, a signal classification module 420, a signal filtering module 430 and a signal combining module 440, wherein the step S101 of the method may be executed by the signal acquisition module 410: and when receiving the multi-path carrier signals, acquiring multi-path frequency band information of the multi-path carrier signals.

Specifically, when the signal processing device receives the multi-path carrier signal output by the radio frequency communication device, the signal acquisition module firstly acquires multi-path frequency band information of the multi-path carrier signal.

The multi-path carrier signal includes at least two paths of carrier signals, and each path of carrier signal has a pre-configured signal frequency band, for example, a B1 frequency band, a B2 frequency band, a B3 frequency band, or a B4 frequency band, etc., it should be understood that the signal frequency bands of the two paths of carrier signals may be partially overlapped or completely separated. Illustratively, the multi-carrier signal may include a first carrier signal with a signal band of B4, a second carrier signal with a signal band of B9, and a third carrier signal with a signal band of B12.

In some embodiments, acquiring the multipath band information of the multipath carrier signal specifically includes: and receiving the multipath frequency band information of the multipath carrier signals output by the radio frequency communication device and/or the signal receiving and transmitting device. Specifically, the multi-channel frequency band information of the multi-channel carrier signal may be determined during the process that the radio frequency communication device performs frequency handshake with the external device through the signal processing device and the signal transceiver, that is, when the radio frequency communication device outputs the multi-channel carrier signal to the signal processing device, at least one of the radio frequency communication device and the signal transceiver determines the multi-channel frequency band information of the multi-channel carrier signal and outputs corresponding information to the signal processing device so as to inform the multi-channel frequency band information of the multi-channel carrier signal, so that when the multi-channel carrier signal output by the radio frequency communication device is received, the signal processing device can determine the multi-channel frequency band information of the multi-channel carrier signal through the radio frequency communication device and/or the signal transceiver.

Step S102, when the multi-channel frequency band information is matched with a preset interference frequency band, classifying the multi-channel carrier signals according to the interference frequency band to obtain a first type carrier signal and a second type carrier signal, wherein the first type carrier signal is at least two carrier signals with signal frequency bands interfering with each other in the multi-channel carrier signal.

It should be understood that the preset interference frequency band is a frequency band combination formed by a plurality of frequency bands which are configured in advance, and signals of the plurality of frequency bands in the frequency band combination have interference with each other when being transmitted simultaneously, wherein the interference condition of carrier signals of different frequency bands with each other when being transmitted simultaneously can be determined through testing. It should also be understood that there is a partial overlap between the signal bands or frequency doubling bands corresponding to the two carrier signals that may interfere with each other during simultaneous transmission.

For example, step S102 of the present application may be performed by a signal classification module in the signal processing device.

Specifically, after the multipath frequency band information of the multipath carrier signals is obtained, the multipath frequency band information is compared with a preset interference frequency band, when the multipath frequency band information is matched with the preset interference frequency band, the signal processing device classifies the multipath carrier signals according to the interference frequency band to obtain a first type carrier signal and a second type carrier signal, wherein the first type carrier signal is at least two paths of carrier signals with signal frequency bands interfering with each other in the multipath carrier signals, and the second type carrier signal is a carrier signal with no interference with each other in the multipath carrier signals, namely, any one of the second type carrier signals cannot interfere with other carrier signals in the multipath carrier signals.

The multi-carrier signal includes a first carrier signal with a signal band of B4, a second carrier signal with a signal band of B9, and a third carrier signal with a signal band of B12, wherein a range of a transmission band corresponding to the B4 band is 1710MHZ-1755MHZ, a range of a transmission band corresponding to the B9 band is 1749.9MHZ-1784.9MHZ, and a range of a transmission band corresponding to the B12 band is 2097MHZ-2148MHZ. The transmitting frequency band corresponding to the B4 frequency band and the transmitting frequency band corresponding to the B9 frequency band are overlapped in part, and the B12 frequency band is not overlapped with the B4 frequency band and the B9 frequency band. It is easy to know that the B4 frequency band and the B9 frequency band are included in a preset interference frequency band, and the multipath carrier signals are classified according to the interference frequency band, so that the signal frequency bands of the first type carrier signals are the B4 frequency band and the B9 frequency band, and therefore the first carrier signals and the second carrier signals are classified as the first type carrier signals, and the third carrier signals are classified as the second type carrier signals.

Step S103, filtering the first type carrier signals to obtain filtered signals.

Specifically, after the multi-path carrier signals are classified according to the interference frequency band to obtain a first type carrier signal and a second type carrier signal, the signal processing device performs filtering processing on the first type carrier signal to obtain a filtered signal, and it is known that the filtering processing on the first type carrier signal is specifically performed on at least one path of carrier signal in the first type filtered signal, so that signals on at least one path of carrier signal partial signal frequency band are filtered, and therefore partial signals with overlapping signal frequency bands or frequency doubling frequency bands in the first type carrier signal are eliminated.

As shown in fig. 3, in some embodiments, step S103 performs filtering processing on the first type carrier signal to obtain a filtered signal, which includes sub-step S1033-sub-step S1033:

step S1031, determining signal frequency band overlapping parts of at least two first-type carrier signals as interference frequency bands;

sub-step S1032 filters out signals in the interference frequency band from the at least one first type carrier signal.

For example, step S103 of the present application may be performed by a signal filtering module in the signal processing device.

As shown in fig. 4, in some embodiments, the signal filtering module 230 at least includes a multiplexer 231, and the multiplexer 231 is provided with multiple filtering channels 231 corresponding to multiple signal frequency bands respectively. When the signal filtering module 230 performs filtering processing on the first type of carrier signal to obtain a filtered signal, the method specifically includes:

the filtering channel 231 controlling at least one corresponding interference frequency band filters out signals in the interference frequency band in the corresponding first carrier signals.

Specifically, each filtering channel is preconfigured to receive a carrier signal of a corresponding signal frequency band, where the signal frequency bands corresponding to the filtering channels of each channel may be separated from each other or there may be partial frequency band overlapping, and the multiple carrier signals include a first type carrier signal and a second type carrier signal. When the signal processing device receives the input multi-channel carrier signals, the signal processing device firstly controls the filtering channel to receive carrier signals corresponding to the frequency bands, then determines a first target channel corresponding to the first type carrier signals in the multi-channel filtering channel, wherein the signal frequency band corresponding to the first target channel is matched with the signal frequency band of the first type carrier signals, and then controls at least one first target channel to perform preset filtering processing on the input first type carrier signals to obtain the filtering signals.

The multipath filtering channels include three filtering channels with corresponding signal frequency bands of B4 frequency band, B9 frequency band and B12 frequency band, and the signal frequency bands of the first type carrier signal are B4 frequency band and B9 frequency band, so that the filtering channel with the corresponding signal frequency band of B4 frequency band and the filtering channel with the corresponding signal frequency band of B4 frequency band are used as the first target channel.

It should be understood that at least two first target channels are determined in the multipath filtering channels, and partial frequency band overlapping exists between signal frequency bands or frequency doubling frequency bands corresponding to at least two first target channels, where the first target channels are used to filter signals on at least one carrier signal partial signal frequency band, so as to eliminate partial signals with overlapping signal frequency bands or frequency doubling frequency bands in the first carrier signals, that is, the radio frequency communication device may control one first target channel to filter partial signals with overlapping frequency bands, and may also control two or more first target channels to filter partial signals with overlapping frequency bands. For example, when the first target channel includes a filtering channel of the B4 band and a filtering channel of the B9 band, the B4 band and the B9 band have 1749.9MHZ-1755MHZ bands overlapping each other, the radio frequency communication device may control at least one of the filtering channels of the B4 band and the filtering channel of the B9 band to filter signals of 1749.9MHZ-1755MHZ bands in the input carrier signal, and may also control the filtering channels of the B4 band and the filtering channel of the B9 band to filter partial signals in the input carrier signal, respectively, where a union of the signal bands filtered by the filtering channels of the B4 band and the signal bands filtered by the filtering channels of the B9 band is 1749.9MHZ-1755 MHZ.

By eliminating partial signals with overlapping signal frequency bands or frequency doubling frequency bands in the first type carrier signals, the filtering processing of the first type carrier signals is realized, so that filtering signals are obtained, interference influence of carrier signals during simultaneous transmission of multiple carrier signals can be eliminated, and filtering performance of the signal processing device is improved.

Further, after determining the signal band overlapping portion of the at least two carrier signals of the first type as the interference band in the substep S1031, the method further comprises: and determining a second target channel corresponding to the second type of carrier signals in the multipath filtering channel, wherein the signal frequency band corresponding to the second target channel is matched with the signal frequency band of the second type of carrier signals, namely the carrier signals received by the second target channel do not need to be subjected to filtering processing, and the second target channel in the multiplexer is used for receiving the carrier signals corresponding to the frequency band and outputting the carrier signals corresponding to the frequency band to the signal receiving and transmitting device, namely the second target channel directly outputs the received second type of carrier signals to the signal receiving and transmitting device.

Further, the signal processing device further includes a controller, at least electrically connected to the multiplexer, for controlling the signal processing device to execute the signal processing method provided in any embodiment of the present application.

signals in the corresponding specific sub-frequency band are filtered out.

Specifically, when the signal processing device executing the method filters signals in the interference frequency band in the first carrier signal, firstly, a specific sub-frequency band matched with the interference frequency band is determined, and it is understood that the specific sub-frequency band matched with the interference frequency band specifically belongs to the sub-frequency band under the interference frequency band, and after the specific sub-frequency band is determined, the signal processing device filters signals in the corresponding specific sub-frequency band.

As shown in fig. 4, in some embodiments, the filtering channel 231 is provided with a plurality of traps 2312 for filtering different specific sub-band signals, and a gating switch 2313 connected to the plurality of traps 2312, where the plurality of traps 2312 are arranged in parallel in the same filtering channel 231 or the same first target channel, and the filtering channel for controlling at least one corresponding interference band filters a signal in an interference band in a corresponding first carrier signal, including:

It should be noted that the plurality of traps 2312 arranged in parallel are respectively connected to the gating switch 2313, and the gating switch 2313 can configure the traps 2312 connected thereto to control the target trap to work so as to filter out the signals in the corresponding specific sub-frequency band, thereby filtering out the signals in the interference frequency band in the first carrier signal.

Specifically, when the signal processing device controls the filtering channel of at least one corresponding interference frequency band to filter the signal in the interference frequency band in the corresponding first type carrier signals, firstly, determining the overlapping part of the signal frequency bands of at least two first type carrier signals as the interference frequency band, for example, using the 1749.9MHZ-1755MHZ frequency band in which the B4 frequency band and the B9 frequency band overlap each other as the interference frequency band. After the interference frequency band is determined, a target trap is determined in a plurality of traps of at least one first target channel according to the interference frequency band, wherein a specific sub-band corresponding to the target trap is matched with the interference frequency band, then a gating switch is controlled, the target traps in the plurality of traps are configured to work so that the target trap receives and filters signals corresponding to the specific sub-band, and in the plurality of traps of the first target channel, other traps except the target trap are controlled to receive the signals corresponding to the specific sub-band but not filter the signals and output signals corresponding to the specific sub-band, and signals output by at least one other trap form a filtering signal, so that the target trap can filter the signals corresponding to the specific sub-band, the other traps except the target trap keep the signals corresponding to the specific sub-band, the filtering accuracy of the multiplexer is ensured, and the filtering performance of the signal processing device is improved.

It should be understood that, in the same filtering channel or the same first target channel, the specific sub-frequency bands corresponding to each trap may be separated from each other, or there may be partial frequency band overlapping, and the union of the signal frequency bands corresponding to all the target traps in the first target channel is an interference frequency band, after determining at least one target trap, the target trap is controlled to filter the input signal, where the signal input to the target trap corresponds to the specific sub-frequency band. In an exemplary case where the interference frequency band is 1749.9MHZ-1755MHZ, the union of the specific sub-bands corresponding to all the target traps should be 1749.9MHZ-1755MHZ, and all the target traps are controlled to filter the signals corresponding to the specific sub-bands, so that the preset filtering processing is completed on the input first carrier signal, and the signals output by other traps are obtained as filtering signals.

As shown in fig. 3, in some embodiments, before sub-step S1033 of step S103, further comprises:

step S1031, determining a target frequency band according to the multipath frequency band information;

in the substep S1032, a preset amplifying process is performed on the carrier signal in the target frequency band in the multiple carrier signals.

As shown in fig. 4 to 5, in some embodiments, the signal filtering module 230 further includes multiple amplifying channels 232 respectively corresponding to multiple signal frequency bands, and the amplifying channels 232 are connected to the filtering channels 231 corresponding to the signal frequency bands; the signal filtering module 2311 further includes, before determining the overlapping signal frequency band portion of the at least two first type carrier signals as the interference frequency band:

the amplifying channels 232 corresponding to the target frequency bands are controlled to perform preset amplifying processing on the carrier signals in the target frequency bands in the multi-channel carrier signals.

Specifically, the signal filtering module firstly determines a target frequency band according to the multi-frequency band information, then controls an amplifying channel corresponding to the target frequency band to perform preset amplifying processing on carrier signals in the target frequency band in the multi-frequency carrier signals, and controls the amplifying channel corresponding to the target frequency band to output the amplified carrier signals to a filtering channel corresponding to the frequency band.

It should be understood that the signal strength of the multi-carrier signal output from the rf communication device to the multiplexer is smaller than the signal strength of the combined signal actually output from the signal transceiver to the external device, so that the multi-carrier signal needs to be amplified. Based on the above, the signal processing device sets an amplifying channel between the radio frequency communication device and each filtering channel, so as to amplify the multi-carrier signal output by the radio frequency communication device, and output the amplified multi-carrier signal to the corresponding filtering channel.

Specifically, the signal processing device determines a target frequency band according to the multi-frequency band information, wherein the target frequency band is a frequency band used by the radio frequency communication device and the signal transceiver device for multi-carrier signal interaction, then the amplifying channel is controlled to receive carrier signals corresponding to the target frequency band in the multi-carrier signals, amplify the carrier signals, and then output the amplified carrier signals to the filtering channel corresponding to the frequency band, namely, the amplifying channel corresponding to the signal frequency band outside the target frequency band cannot output the amplified carrier signals to the corresponding filtering channel.

As shown in fig. 6, in some embodiments, the amplifying channel 232 includes a power amplifier 2321 and a power amplifying switch 2322, where the power amplifier 2321 is configured to receive an input multiple carrier signal, where the multiple carrier signal may include a first type carrier signal and a second type carrier signal, and the other end is connected to the filtering channel 410 through the power amplifying switch 2322, and the power amplifier 2321 is configured to amplify a signal strength of the carrier signal input to the amplifying channel 232 and output the amplified carrier signal to the corresponding filtering channel through the power amplifying switch. It should be noted that, when the power amplifying switch 2322 is in the on state, the amplified carrier signal may be output to the corresponding filtering channel 410 through the power amplifying switch 2322, and when the power amplifying switch 2322 is in the off state, the amplified carrier signal may not be output to the corresponding filtering channel 410 through the power amplifying switch.

The step of controlling the amplifying channel corresponding to the signal frequency band to output the amplified carrier signal to the filtering channel corresponding to the frequency band specifically comprises the following steps:

determining an amplification channel corresponding to a signal frequency band as a first target amplification channel;

and controlling the power amplification switch in the first target amplification channel to be conducted so that the power amplifier outputs the amplified carrier signal to the filtering channel.

Specifically, the signal processing device firstly determines an amplifying channel corresponding to a signal frequency band as a first target amplifying channel, and then controls a power amplifying switch in the first target amplifying channel to be switched to a conducting state so that the power amplifier outputs an amplified carrier signal to the filtering channel. Further, the signal processing device switches the power amplifying switch of the amplifying channel other than the first target amplifying channel to the off state.

For example, when the target frequency band of the multi-path carrier signal includes a B4 frequency band, a B9 frequency band, and a B12 frequency band, the signal processing apparatus uses amplification channels corresponding to the B4 frequency band, the B9 frequency band, and the B12 frequency band as the first target amplification channel, and controls the power amplification switch in the first target amplification channel to switch to a conductive state, so that the carrier signals of the B4 frequency band, the B9 frequency band, and the B12 frequency band are amplified and output to the corresponding filtering channels.

Step S104, generating a combined signal according to the filtered signal and the second carrier signal.

After the first type of filtering signal is filtered to obtain a filtering signal, the signal processing device generates a combined signal according to the filtering signal and the second type of carrier signal, specifically, the signal processing device receives the filtering signal output by the first target channel and the second type of carrier signal output by the second target channel, performs the combined processing on the filtering signal and the second type of carrier signal to generate a combined signal, and after the combined signal is generated, the signal processing device outputs the combined signal to the signal transceiver device so that the signal transceiver device outputs the combined signal to external equipment.

For example, step S104 of the present application may be performed by a signal combining module in the signal processing device.

As shown in fig. 7, in some embodiments, the signal combining module 240 includes a multi-frequency device 241, where an input end of the multi-frequency device 241 is connected to the plurality of filtering channels 231, and the multi-frequency device 241 is configured to receive the filtered signal output by the first target channel and the second carrier signal output by the second target channel, combine the filtered signal with the second carrier signal to generate a combined signal, and output the combined signal from the output end to the signal transceiver or the radio frequency communication device. For example, when the signal transceiver 400 is an antenna and the multi-frequency band 241 outputs the combined signal to the signal transceiver 400, the antenna multi-frequency band may be used as the multi-frequency band 241 connected to the antenna.

In some embodiments, step S104 generates a combined signal according to the filtered signal and the second carrier signal, and specifically includes:

As shown in fig. 7, taking the signal filtering module to execute the step S104 as an example, the signal filtering module 240 further includes a plurality of phase shifters 243 corresponding to the plurality of filtering channels 231, respectively, wherein the corresponding phase shifters 243 are connected between the corresponding filtering channels 231 and the same multi-frequency channel 241. The signal filtering module 240, when generating a combined signal according to the filtered signal and the second carrier signal, specifically includes:

the phase shifters 243 corresponding to the control signal frequency bands respectively perform corresponding phase shifting processing on the filtered signals and the second carrier signals so as to enable the phase difference between the signals of any two frequency bands in the filtered signals and the second carrier signals to be in a preset target phase difference range;

The multi-frequency controller 241 is controlled to perform a combining process on the filtered signal after the phase shift process and the second carrier signal to obtain a combined signal.

Further, the signal combining module 240 further includes a plurality of switch units 242 disposed corresponding to the plurality of filtering channels 231. The signal processing apparatus 200 may control on and off of the branch where each phase shifter 243 is located through the corresponding switch unit 242, specifically, control on of the switch unit 242 where the corresponding signal frequency band is located in the target frequency band, and control off of the switch unit 242 in the filter channel 231 where the corresponding signal frequency band is located outside the target frequency band, so that the filter channel 231 where the corresponding signal frequency band is located in the target frequency band outputs the signal reserved by the trap set to the phase shifter 243. The signal processing apparatus 200 is further configured to control the at least one phase shifter 243 to perform phase shifting processing on the signal received by the phase shifter 243 to adjust the phase difference of the signals output by the plurality of filtering channels 231, so that the phase difference between the filtered signal and the signals of any two frequency bands in the second carrier signal is within a preset target phase difference range, and then output the phase-shifted signal as a filtered signal to the multifrequesters 241, so as to significantly improve the combining effect of the multifrequesters 241 on the combining processing of the filtered signal and the second carrier signal, and eliminate the interference caused by the simultaneous transmission of multiple signals.

It should be understood that, the radio frequency communication device outputs a communication signal to the signal transceiver device through the signal processing device, and the signal transceiver device outputs a communication signal to the radio frequency communication device through the signal processing device may be performed simultaneously, that is, communication interaction between the radio frequency communication device and the signal transceiver device may be performed in two directions and in parallel, and the signal processing method provided in the application may also be applied to a scenario that the radio frequency communication device outputs a first multi-path carrier signal to the signal transceiver device through the signal processing device, and the signal transceiver device outputs a second multi-path carrier signal to the radio frequency communication device through the signal processing device.

The following specifically describes a scenario in which the radio frequency communication device outputs a first multi-carrier signal to the signal transceiver device through the signal processing device, and the signal transceiver device outputs a second multi-carrier signal to the radio frequency communication device through the signal processing device.

Specifically, when the radio frequency communication device outputs a first multi-path carrier signal to the signal receiving and transmitting device through the signal processing device and the signal receiving and transmitting device outputs a second multi-path carrier signal to the radio frequency communication device through the signal processing device, the signal processing device obtains multi-path frequency band information of the multi-path carrier signal. The multi-channel frequency band information of the multi-channel carrier signal at least comprises first multi-channel frequency band information of the first multi-channel carrier signal and second multi-channel frequency band information of the second multi-channel carrier signal.

After the multi-channel frequency band information is obtained, the first multi-channel frequency band information, the second multi-channel frequency band information and the preset interference frequency band are compared, when the combination of the first multi-channel frequency band information and the second multi-channel frequency band information is matched with the preset interference frequency band, multi-channel carrier signals are classified according to the interference frequency band to obtain a first carrier signal and a second carrier signal, wherein the first carrier signal is at least two carrier signals with signal frequency bands interfering with each other in the multi-channel carrier signals, then the first carrier signal is filtered to obtain a filtered signal, and a combined signal is generated according to the filtered signal and the second carrier signal.

For example, when the multiple carrier signals output by the radio frequency communication device include carrier signals in B12 frequency band and the multiple received signals output by the signal transceiver device include received signals in B4 frequency band, the range of the received frequency band corresponding to B4 frequency band is 2110MHZ-2155MHZ, the range of the transmitted frequency band corresponding to B12 frequency band is 699MHZ-716MHZ, and the range of the tripled frequency corresponding to the transmitted frequency band is 2097MHZ-2148MHZ, so that the tripled frequency of the transmitted frequency band in B12 frequency band and the B4 frequency band have 2097MHZ-2148MHZ overlapping each other, which may cause interference to the signal in B4 frequency band received by the radio frequency communication device. Based on this, the signal processing apparatus uses the carrier signal of the B12 band and the received signal of the B4 band, which interfere with each other, as the fifth type carrier signal, and performs filtering processing on one of the two types of carrier signals to eliminate the frequency band overlapping of the two types of carrier signals occurring in the 2097MHZ-2148MHZ band, thereby eliminating interference generated by the signal processing apparatus between the two types of signals when the carrier signal of the B12 band and the received signal of the B4 band are transmitted simultaneously.

By eliminating partial signals with overlapping signal frequency bands or frequency doubling frequency bands in the first carrier signals to obtain filtering signals, interference influence of the carrier signals during simultaneous transmission of multiple carrier signals can be eliminated, and filtering performance and carrier aggregation performance of the signal processing device are improved.

In summary, the signal processing method provided in the above embodiment includes: when receiving a multi-channel carrier signal, acquiring multi-channel frequency band information of the multi-channel carrier signal, classifying the multi-channel carrier signal according to an interference frequency band when the multi-channel frequency band information is matched with a preset interference frequency band to obtain a first type carrier signal and a second type carrier signal, wherein the first type carrier signal is at least two paths of carrier signals with signal frequency bands interfering with each other in the multi-channel carrier signal, and then filtering the first type carrier signal to obtain a filtered signal; and generating a combined signal according to the filtering signal and the second type carrier signal, thereby realizing the integration of the transmission of the multi-path carrier signals, eliminating the interference influence of the carrier signals when the multi-path carrier signals are transmitted simultaneously, and improving the filtering performance of the signal processing device.

Referring to fig. 2, fig. 2 is a schematic block diagram of a signal processing apparatus according to an embodiment of the present invention.

As shown in fig. 2, the present application further provides a signal processing apparatus 200, where the signal processing apparatus 200 includes: an information acquisition module 210, a signal classification module 220, a signal filtering module 230 and a signal combining module 240.

Specifically, when the information obtaining module 210 is configured to receive multiple carrier signals, multiple frequency band information of the multiple carrier signals is obtained, the signal classifying module 220 is configured to classify the multiple carrier signals according to the interference frequency band when the multiple frequency band information is matched with a preset interference frequency band, so as to obtain a first type carrier signal and a second type carrier signal, where the first type carrier signal is at least two carrier signals with signal frequency bands interfering with each other in the multiple carrier signals, the signal filtering module 230 is configured to perform filtering processing on the first type carrier signal to obtain a filtered signal, and the signal combining module 240 is configured to generate a combined signal according to the filtered signal and the second type carrier signal.

In some embodiments, the signal processing apparatus provided herein includes a matching circuit, a radio frequency power amplifier, a low noise amplifier, a multiplexing filter, a phase shifter, a switching unit, and a multi-frequency. It should be noted that the matching circuit, the rf power amplifier, the low noise amplifier, the multiplexing filter, the gating switch, the phase shifter, the switching unit and the multiple frequency band are integrally packaged in the same device to be used as the signal processing device, so that the integration level of the signal processing device is improved, and the volume of the signal processing device is reduced.

Specifically, when a radio frequency communication device, such as a radio frequency chip, inputs multiple carrier signals to a signal processing device, the signal processing device acquires multiple frequency band information of the multiple carrier signals, compares the multiple frequency band information with a preset interference frequency band through a matching circuit, and classifies the multiple carrier signals into a first type carrier signal and a second type carrier signal according to the interference frequency band when the multiple frequency band information is matched with the interference frequency band. After the first type of carrier signals are determined, the radio frequency power amplifier is used as an amplifying channel, the first type of carrier signals and the second type of carrier signals are input into the radio frequency power amplifier for amplifying, the carrier signals in the target frequency band in the multipath carrier signals are subjected to preset amplifying, the first type of carrier signals are subjected to filtering through a multiplexing filter comprising a plurality of filtering channels, and particularly, at least one filtering channel corresponding to the interference frequency band is controlled to filter the signals in the interference frequency band in the corresponding first type of carrier signals, so that the filtering signals are obtained. After that, the signal processing device respectively performs corresponding phase shifting processing on the filtered signal and the second carrier signal through the phase shifter, so that the phase difference between the filtered signal and the signals of any two frequency bands in the second carrier signal is in a preset target phase difference range, and controls the switch unit of the corresponding signal frequency band in the target frequency band to be conducted, so that the filtered signal and the signals of the second carrier signal in the target frequency band are output, and the output signals of the second carrier signal in the target frequency band are subjected to path combination processing through the multifrequency to obtain a combined signal. It should be noted that when the signal transceiver is an antenna device, the multiple frequency band may be an antenna multiple frequency band. The signal processing device outputs the processed combined signal to the signal transmitting/receiving device so that the signal transmitting/receiving device, which is, for example, an antenna device, transmits the combined signal to an external device.

Specifically, when the signal transceiver of the antenna device inputs multiple carrier signals to the signal processing device, the signal processing device obtains multiple frequency band information of the multiple carrier signals, compares the multiple frequency band information with a preset interference frequency band through the matching circuit, and classifies the multiple carrier signals into a first carrier signal type and a second carrier signal type according to the interference frequency band when the multiple frequency band information is matched with the interference frequency band. After the first type of carrier signals are determined, the low-noise amplifier is used as an amplifying channel, the first type of carrier signals and the second type of carrier signals are input into the low-noise amplifier for amplifying, the carrier signals in the target frequency band in the multipath carrier signals are subjected to preset amplifying, the first type of carrier signals are subjected to filtering through a multiplexing filter comprising a plurality of filtering channels, and particularly, at least one filtering channel corresponding to the interference frequency band is controlled to filter the signals in the interference frequency band in the corresponding first type of carrier signals, so that the filtering signals are obtained. After that, the signal processing device respectively performs corresponding phase shifting processing on the filtered signal and the second carrier signal through the phase shifter, so that the phase difference between the filtered signal and the signals of any two frequency bands in the second carrier signal is in a preset target phase difference range, and controls the switch unit of the corresponding signal frequency band in the target frequency band to be conducted, so that the filtered signal and the signals of the second carrier signal in the target frequency band are output, and the output signals of the second carrier signal in the target frequency band are subjected to path combination processing through the multifrequency to obtain a combined signal. The signal processing device outputs the processed combined signal to the radio frequency communication device, so that the radio frequency communication device, such as a radio frequency chip, receives the combined signal.

As shown in fig. 8, the embodiment of the present invention further provides a communication device 500, where the communication device 500 includes a radio frequency communication apparatus 300, a signal transceiver apparatus 400, and a signal processing apparatus 200. Specifically, the signal processing device 200 is communicatively connected to the radio frequency front-end device and the signal transceiver 400. The signal processing device is used for executing any signal processing method provided by the specification of the application, wherein the radio frequency communication device is used for outputting multi-path carrier signals to the signal processing device, and the signal receiving and transmitting device is used for receiving the combined signals generated by the signal processing device. Or, the signal transceiver is used for outputting the multi-path carrier signals to the signal processing device, and the radio frequency communication device is used for receiving the combined signals generated by the signal processing device. Illustratively, the communication device 500 includes, but is not limited to, a mobile communication device and a communication base station, with the communication device being used to enable communication interactions with external devices.

The signal processing device may be any signal processing device as provided by an embodiment of the present invention.

Specifically, the radio frequency communication device is, for example, a radio frequency chip for outputting a carrier signal and acquiring a received signal, the signal receiving and transmitting device is, for example, an antenna, the signal processing device is, for example, a radio frequency front end device, the radio frequency communication device can output a communication signal to an external device through the signal processing device and the signal receiving and transmitting device, and the communication signal output by the external device to the communication device can be transmitted to the radio frequency communication device through the signal receiving and transmitting device and the signal processing device, so as to realize communication interaction between the communication device and the external device, and the signal processing device is specifically used for amplifying and filtering the signal transmitted from the radio frequency communication device to the signal receiving and transmitting device or the signal transmitted from the signal receiving and transmitting device to the radio frequency communication device, so as to realize integration of multi-carrier signal transmission, eliminate interference influence of carrier signals when the multi-carrier signals are transmitted simultaneously, and improve filtering performance of the signal processing device.

Those of ordinary skill in the art will appreciate that all or some of the steps, systems, functional modules/units in the apparatus, and methods disclosed above may be implemented as software, firmware, hardware, and suitable combinations thereof. In a hardware embodiment, the division between the functional modules/units mentioned in the above description does not necessarily correspond to the division of physical components; for example, one physical component may have multiple functions, or one function or step may be performed cooperatively by several physical components. Some or all of the physical components may be implemented as software executed by a processor, such as a central processing unit, digital signal processor, or microprocessor, or as hardware, or as an integrated circuit, such as an application specific integrated circuit. Such software may be distributed on computer readable media, which may include computer storage media (or non-transitory media) and communication media (or transitory media). The term computer storage media includes both volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of information such as computer readable instructions, data structures, program modules or other data, as known to those skilled in the art. Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory media, CD-ROM, digital Versatile Disks (DVD) or other optical disk storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to store the desired information and which can be accessed by a computer. Furthermore, as is well known to those of ordinary skill in the art, communication media typically embodies computer readable instructions, data structures, program modules or other data in a modulated data signal such as a carrier wave or other transport mechanism and includes any information delivery media.

It should be understood that the term "and/or" as used in the present specification and the appended claims refers to any and all possible combinations of one or more of the associated listed items, and includes such combinations. It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or system. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article, or system that comprises the element.

The foregoing embodiment numbers of the present invention are merely for the purpose of description, and do not represent the advantages or disadvantages of the embodiments. While the invention has been described with reference to certain preferred embodiments, it will be understood by those skilled in the art that various changes and substitutions may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. Therefore, the protection scope of the invention is subject to the protection scope of the claims.

Claims

1. A signal processing method, comprising:

when receiving a multi-channel carrier signal, acquiring multi-channel frequency band information of the multi-channel carrier signal;

when the multi-channel frequency band information is matched with a preset interference frequency band, classifying the multi-channel carrier signals according to the interference frequency band to obtain a first type carrier signal and a second type carrier signal, wherein the first type carrier signal is at least two paths of carrier signals with signal frequency bands interfering with each other in the multi-channel carrier signal;

filtering the first type carrier signals to obtain filtered signals;

and generating a combined signal according to the filtered signal and the second type carrier signal.

2. The signal processing method according to claim 1, wherein the filtering the first type carrier signal to obtain a filtered signal includes:

and filtering signals in the interference frequency band in at least one carrier signal of the first type.

3. The signal processing method according to claim 2, wherein filtering out signals in the interference frequency band from at least one of the first type carrier signals comprises:

Determining a specific sub-band matched with the interference band;

signals in the corresponding specific sub-frequency band are filtered out.

4. The signal processing method according to claim 2, wherein before determining the signal band overlapping portions of at least two of the first type carrier signals as interference bands, further comprising:

determining a target frequency band according to the multi-path frequency band information;

and carrying out preset amplification processing on the carrier signals in the target frequency band in the multi-channel carrier signals.

5. The signal processing method according to any one of claims 1 to 4, wherein generating a combined signal from the filtered signal and the second type carrier signal comprises:

respectively carrying out corresponding phase shifting treatment on the filtering signal and the second type carrier signal so as to enable the phase difference between the filtering signal and the signals of any two frequency bands in the second type carrier signal to be in a preset target phase difference range;

and combining the phase-shifted filtered signal with the second carrier signal to obtain the combined signal.

6. A signal processing apparatus, comprising:

The signal classification module is used for classifying the multi-channel carrier signals according to the interference frequency bands when the multi-channel frequency band information is matched with the preset interference frequency bands to obtain first-class carrier signals and second-class carrier signals, wherein the first-class carrier signals are at least two paths of carrier signals with signal frequency bands interfering with each other in the multi-channel carrier signals;

and the signal combining module is used for generating a combined signal according to the filtered signal and the second type carrier signal.

7. The signal processing device according to claim 6, wherein the signal filtering module comprises a multiplexer, and the multiplexer is provided with multiple filtering channels corresponding to multiple signal frequency bands respectively;

the signal filtering module performs filtering processing on the first type carrier signals to obtain filtered signals, and the signal filtering module comprises:

and controlling at least one filtering channel corresponding to the interference frequency band to filter signals in the interference frequency band in the corresponding first type carrier signals.

8. The signal processing apparatus according to claim 7, wherein the filtering channel is provided with a plurality of traps for filtering out different specific sub-band signals, respectively, and a gating switch for connecting with the plurality of traps;

the controlling the filtering channel corresponding to the interference frequency band to filter the signal in the interference frequency band in the corresponding first carrier signal includes:

determining a target trap matched with the corresponding specific sub-frequency band and the interference frequency band in at least one filtering channel corresponding to the interference frequency band;

and controlling the target trap to work through the gating switch so that the target trap filters signals in a corresponding specific sub-frequency band.

9. The signal processing device according to claim 6, wherein the signal filtering module further comprises a plurality of amplifying channels respectively provided corresponding to a plurality of signal frequency bands, and the amplifying channels are connected with the filtering channels corresponding to the signal frequency bands;

before determining the signal frequency band overlapping part of at least two carrier signals of the first type as an interference frequency band, the method further comprises:

And controlling the amplifying channel corresponding to the target frequency band to perform preset amplifying processing on the carrier signals in the target frequency band in the multi-channel carrier signals.

10. The signal processing device according to any one of claims 6-9, wherein the signal combining module includes a plurality of frequency bands and a plurality of phase shifters respectively disposed corresponding to a plurality of the signal frequency bands, and the generating a combined signal according to the filtered signal and the second type carrier signal includes:

controlling the phase shifter corresponding to the signal frequency band to respectively perform corresponding phase shifting processing on the filtered signal and the second type carrier signal so as to enable the phase difference between the signals of any two frequency bands in the filtered signal and the second type carrier signal to be in a preset target phase difference range;

and controlling the multifrequesters to perform combining processing on the filtered signals after the phase shift processing and the second type carrier signals to obtain the combined signals.

11. The signal processing device according to any one of claims 6-9, wherein the signal processing device comprises an integrated package of a matching circuit, a radio frequency power amplifier, a low noise amplifier, a multiplexing filter, a phase shifter, a switching unit and a multi-frequency.

12. A communication device, characterized in that the communication device comprises radio frequency communication means, signal transceiving means and signal processing means connecting the radio frequency communication means and the signal transceiving means, the signal processing means being adapted to perform the signal processing method according to any of claims 1-5;

the radio frequency communication device is used for outputting the multi-path carrier signals to the signal processing device, and the signal receiving and transmitting device is used for receiving the combined signals generated by the signal processing device; or (b)

The signal transceiver is used for outputting the multi-path carrier signals to the signal processing device, and the radio frequency communication device is used for receiving the combined signals generated by the signal processing device.