Gateway system based on linear frequency modulation signal

Abstract

The present invention relates to the technical field of communications, and provides a gateway system based on a linear frequency modulation signal, comprising: at least one group of receiving channels, wherein each group of receiving channels comprises a plurality of receiving chips, one of the receiving chips is respectively connected to one receiving antenna and the remaining receiving chips, and the receiving chip connected to the receiving antenna is used for distributing a linear frequency modulation signal received by the receiving antenna to the corresponding receiving chip for demodulation, so as to output a plurality of demodulated linear frequency modulation signals of different frequency bands. The present invention has the beneficial effects that the use of antennas can be reduced, no combiner is required, there is no loss of signal energy, and the frequency of receiving chips can be distinguished by configuring a digital intermediate frequency value and a spreading factor.

Description

A gateway system based on linear frequency modulation signal Technical Field

[0001] The present invention relates to the field of communication technology, and in particular to a gateway system based on linear frequency modulation signals. Background Art

[0002] A local area network (LAN) is a network built within a local area. LANs can be large or small, from connecting buildings to small offices. LANs have a limited distribution range, are faster than other networks, offer more stable performance, a simpler architecture, and are closed, making them popular choices for private networks. Linear frequency modulation (LFM) signals are signals whose frequency varies linearly over time. Because the frequency spectrum occupied by LFM signals is much wider than the information bandwidth, they can achieve significant system processing gain. Using LFM signals to transmit data allows for long-distance, low-power transmission, making them particularly suitable for low-speed, wide-area applications. This makes LFM systems a LAN with flexible deployment, low cost, low power consumption, long battery life, and long transmission distances, making them suitable for a wide range of networking needs.

[0003] One existing approach to building gateways uses a multi-antenna architecture, with one chirp signal chip corresponding to one antenna, responsible for both transmission and reception. ChirpLAN, a local area network (LAN) based on chirp signals, uses data daughter cards comprised of multiple chirp signal chips as the transmit and receive paths. This architecture requires a separate antenna for each data daughter card. For example, a system with eight RX channels and two TX channels would require ten antennas.

[0004] To reduce the number of antennas used, existing solutions use combiners, but each combiner results in a 3dB loss. Combiners allow multiple transceiver chips to use a single antenna. One existing solution uses four receive chips using one antenna, employing two combiners to form a receive system. Four transmit chips and two combiners are connected to one antenna to form a transmit system. This solution has the advantage of reducing the number of antennas, from eight receive antennas and two transmit antennas to two receive antennas and one transmit antenna. However, the disadvantage is that the use of combiners reduces the signal-to-noise ratio, impacting the system's coverage.

[0005] Summary of the Invention

[0006] In response to the problems existing in the prior art, the present invention provides a gateway system based on linear frequency modulation signals, including at least one group of receiving channels, each group of receiving channels including multiple receiving chips, one of the receiving chips being connected to a receiving antenna and each of the remaining receiving chips, and the receiving chip connected to the receiving antenna being used to distribute the linear frequency modulation signal received by the receiving antenna to the corresponding receiving chip for demodulation, so as to output multiple demodulated linear frequency modulation signals in different frequency bands.

[0007] Preferably, each of the receiving chips includes an analog-to-digital converter and a digital demodulation module connected in sequence;

[0008] The receiving chip connected to the receiving antenna also includes a signal distribution module, the output of which is respectively connected to the input of the analog-to-digital converter of the receiving chip in which it is located and the input of the analog-to-digital converter of each of the remaining receiving chips, so as to send the linear frequency modulation signal received by the receiving antenna to the corresponding analog-to-digital converter for analog-to-digital conversion and then send it to the digital demodulation module for demodulation to obtain the demodulated linear frequency modulation signal of the corresponding frequency band.

[0009] Preferably, each of the receiving chips is associated with a corresponding preset spreading factor, and the signal distribution module includes:

[0010] a storage unit, configured to store an association between each of the preset spreading factors and each of the receiving chips;

[0011] The first allocation unit is connected to the storage unit and is configured to obtain a real-time spreading factor of the received linear frequency modulation signal and allocate the linear frequency modulation signal to the receiving chip associated with the preset spreading factor matching the real-time spreading factor.

[0012] Preferably, the signal distribution module includes:

[0013] A monitoring unit, configured to monitor the current status of each receiving chip in real time;

[0014] A second allocation unit is connected to the monitoring unit and is used to obtain the real-time spreading factor of the received linear frequency modulation signal, and configure the real-time spreading factor to any of the receiving chips that is currently idle, and then allocate the linear frequency modulation signal to the receiving chip configured with the real-time spreading factor.

[0015] Preferably, each receiving chip is provided with a plurality of bus pins, and the signal distribution module is correspondingly connected to the remaining receiving chips through each bus pin to configure the real-time spreading factor into each receiving chip.

[0016] Preferably, each of the bus pins is an SPI bus pin or an IIC bus pin.

[0017] Preferably, each of the receiving chips further comprises a radio frequency module and an analog filter connected in sequence;

[0018] For the receiving chip connected to the receiving antenna, the radio frequency module thereof is connected to the receiving antenna, and the output of the analog filter is connected to the analog-to-digital converter thereof through the signal distribution module;

[0019] For the remaining receiving chips, the output of the analog filter is connected to the analog-to-digital converter thereof, and the RF module and the analog filter are not working.

[0020] Preferably, the digital demodulation module includes a mixer, a digital filter and a demodulator connected in sequence, and the input of the mixer is connected to the output of the corresponding analog-to-digital converter.

[0021] Preferably, each receiving chip is further provided with a register connected to the mixer and used to store a pre-configured digital intermediate frequency value;

[0022] The mixer is used to perform mixing processing on the digital linear frequency modulation signal obtained by the analog-to-digital converter according to the digital intermediate frequency value.

[0023] The above technical solution has the following advantages or beneficial effects:

[0024] 1) It can reduce the use of antennas, eliminate the need for combiners, and avoid signal energy loss. The frequency of each receiving chip can be distinguished by configuring the digital intermediate frequency value and spreading factor;

[0025] 2) By integrating a signal distribution module into the receiving chip connected to the receiving antenna, it is possible to perform real-time spreading factor identification on the received linear frequency modulation signal and distribute it to an idle receiving chip with a matching preset spreading factor for processing, thus achieving flexible scheduling;

[0026] 3) Only the RF module and analog filter of the receiving chip connected to the receiving antenna are working, while the RF modules and analog filters of the other receiving chips remain in the off state, effectively saving energy consumption;

[0027] 4) In actual application scenarios, multiple receiving chips can be made into a package module to provide greater flexibility in frequency band selection. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] FIG1 is a schematic structural diagram of a gateway system based on a linear frequency modulation signal in a preferred embodiment of the present invention;

[0029] FIG2 is a schematic structural diagram of a signal distribution module in a preferred embodiment of the present invention;

[0030] FIG3 is a structural diagram of a signal distribution module in another preferred embodiment of the present invention. DETAILED DESCRIPTION

[0031] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments. The present invention is not limited to this embodiment, and other embodiments may also fall within the scope of the present invention as long as they conform to the gist of the present invention.

[0032] In a preferred embodiment of the present invention, based on the above-mentioned problems existing in the prior art, a gateway system based on linear frequency modulation signals is provided, as shown in Figure 1, including at least one group of receiving channels, each group of receiving channels including multiple receiving chips, one of which is connected to a receiving antenna 100 and each of the remaining receiving chips. The receiving chip connected to the receiving antenna 100 is used to distribute the linear frequency modulation signal received by the receiving antenna 100 to the corresponding receiving chip for demodulation, so as to output multiple demodulated linear frequency modulation signals of different frequency bands.

[0033] Specifically, the gateway system of the present invention can be configured with one or more groups of receiving channels as needed, each group of receiving channels containing multiple receiving chips. For example, each group of receiving channels contains four receiving chips, as shown in Figure 1, namely receiving chip #1, receiving chip #2, receiving chip #3, and receiving chip #4. Among them, only receiving chip #1 is connected to receiving antenna 100, and the remaining receiving chips do not need to be connected to receiving antenna 100, effectively reducing the number of antennas used. The above-mentioned four receiving chips per receiving channel is only an embodiment of the present invention and does not limit the number of receiving chips to be set.

[0034] Furthermore, the linear frequency modulation signal is distributed to the corresponding receiving chip for demodulation through the #1 receiving chip, so that each receiving chip outputs the demodulated linear frequency modulation signal of a different frequency band, realizing the gateway function without the need to set up a separate combiner, thereby avoiding signal energy loss.

[0035] In a preferred embodiment of the present invention, each receiving chip includes an analog-to-digital converter ADC and a digital demodulation module 200 connected in sequence;

[0036] The #1 receiving chip connected to the receiving antenna 100 also includes a signal distribution module 300. The output of the signal distribution module 300 is connected to the input of the analog-to-digital converter ADC of the #1 receiving chip where it is located and to the input of the analog-to-digital converter ADC of each of the remaining receiving chips, so as to send the linear frequency modulation signal received by the receiving antenna 100 to the corresponding analog-to-digital converter ADC for analog-to-digital conversion and then send it to the digital demodulation module 200 for demodulation to obtain the demodulated linear frequency modulation signal of the corresponding frequency band.

[0037] Specifically, in this embodiment, for linear frequency modulation signals, different spreading factors cannot communicate with each other, similar to orthogonal coding modulation. Therefore, different receiving chips can be distinguished by setting different spreading factors for different receiving chips. Then, the signal distribution module 300 sends the received linear frequency modulation signal to an idle receiving chip capable of processing the linear frequency modulation signal for demodulation based on the spreading factor of the received linear frequency modulation signal. Here, the idle receiving chip capable of processing the linear frequency modulation signal includes the receiving chip where the receiving chip is located. As a preferred embodiment of the present invention, each receiving chip is associated with a corresponding preset spreading factor. The preset spreading factor here can be obtained through pre-configuration. In other words, the number of receiving chips and the corresponding spreading factors can be configured based on which frequency bands the gateway system is desired to support. As shown in FIG. 2 , the signal distribution module 300 includes:

[0038] The storage unit 301 is used to store the association between each preset spreading factor and each receiving chip;

[0039] The first allocating unit 302 is connected to the storage unit 301 and is configured to obtain the real-time spreading factor of the received linear frequency modulation signal and allocate the linear frequency modulation signal to a receiving chip associated with a preset spreading factor matching the real-time spreading factor.

[0040] Specifically, in this embodiment, the signal allocation module 300 can identify the real-time spreading factor of the received linear frequency modulation signal, and then match it with each preset spreading factor based on the real-time spreading factor. The receiving chip associated with the matched preset spreading factor is the receiving chip that can process the linear frequency modulation signal. Furthermore, after allocating the linear frequency modulation signal, the signal allocation module 300 can also record which receiving chip the linear frequency modulation signal is allocated to, and then determine whether each receiving chip is in an idle state, so that the receiving chip that can process the linear frequency modulation signal and is idle can demodulate the linear frequency modulation signal.

[0041] As another preferred embodiment of the present invention, each receiving chip may be configured with a default preset spreading factor, or may not be pre-configured, but configured by the signal distribution module 300 during the use of the gateway system. As shown in FIG3 , the signal distribution module 300 includes:

[0042] The monitoring unit 303 is used to monitor the current status of each receiving chip in real time;

[0043] The second allocation unit 304 is connected to the monitoring unit 303 and is used to obtain the real-time spreading factor of the received linear frequency modulation signal, and configure the real-time spreading factor to any receiving chip that is currently idle, and then allocate the linear frequency modulation signal to the receiving chip configured with the real-time spreading factor.

[0044] Specifically, in this embodiment, the signal distribution module 300 can also identify the real-time spreading factor of the received linear frequency modulation signal, and can also record the current spreading factor of the receiving chip that has been configured with the spreading factor. Then, when a new linear frequency modulation signal is received, the current spreading factor of each receiving chip in the idle state is first determined. If there is a current spreading factor that matches the real-time spreading factor, the signal distribution module 300 can directly distribute the linear frequency modulation signal to the matching receiving chip. If there is no current spreading factor that matches the real-time spreading factor, it means that at this time, although Although there is an idle receiving chip, it cannot process the linear frequency modulation signal. Based on this, the signal allocation module 300 preferably first configures the real-time spreading factor to any idle receiving chip so that it can process the linear frequency modulation signal, and then sends the linear frequency modulation signal to the configured receiving chip for demodulation. At the same time, the signal allocation module 300 updates the recorded current spreading factor of the receiving chip so that new linear frequency modulation signals can be allocated and used later. The process is executed in a loop in sequence, so that the gateway system of the present invention can provide demodulated linear frequency modulation signals of different frequency bands.

[0045] Furthermore, each receiving chip is provided with a plurality of bus pins 400 , and the signal distribution module 300 is connected to the remaining receiving chips via the bus pins 400 to configure the real-time spreading factor to each receiving chip.

[0046] In a preferred embodiment of the present invention, each bus pin 400 is an SPI bus pin or an IIC bus pin.

[0047] In a preferred embodiment of the present invention, each receiving chip further includes a radio frequency module RF module and an analog filter Filter IQ Analog output connected in sequence;

[0048] For the #1 receiving chip connected to the receiving antenna 100, its RF module is connected to the receiving antenna 100, and the output of the analog filter Filter IQ Analog output is connected to its own analog-to-digital converter ADC through the signal distribution module 300;

[0049] For the remaining receiving chips, the output of the analog filter Filter IQ Analog output is connected to its own analog-to-digital converter ADC, and the RF module RF module and the analog filter Filter IQ Analog output are not working.

[0050] Specifically, in this embodiment, as shown in Figure 1, since only the 1# receiving chip is connected to the receiving antenna 100, its corresponding RF module needs to communicate with the receiving antenna 100 to obtain the linear frequency modulation signal received by the receiving antenna 100, and then the analog filter Filter IQ Analog output performs analog filtering on the linear frequency modulation signal to obtain an IQ analog differential signal outputted at the intermediate frequency. Subsequently, the signal distribution module 300 sends it to the analog-to-digital converter ADC of each receiving chip for analog-to-digital conversion and then sends it to the digital demodulation module 200 for demodulation.

[0051] As can be seen, only the RF module and analog filter Filter IQ Analog output of receiver chip #1 are required to perform signal reception and analog filtering. The RF modules and analog filters Filter IQ Analog output of the remaining receiver chips, such as receiver chips #2, #3, and #4 in Figure 1, can be inactive, effectively saving energy. More preferably, the RF module and analog filter Filter IQ Analog output of the remaining receiver chips, such as receiver chips #2, #3, and #4 in Figure 1, can be omitted, further saving chip production costs.

[0052] In a preferred embodiment of the present invention, the digital demodulation module 200 includes a mixer, a digital filter, and a demodulator, which are connected in sequence. The input of the mixer is connected to the output of the corresponding analog-to-digital converter ADC.

[0053] In a preferred embodiment of the present invention, each receiving chip is further provided with a register 500 connected to the mixer for storing a pre-configured digital intermediate frequency value;

[0054] The mixer is used to mix the digital linear frequency modulation signal obtained by the analog-to-digital converter ADC according to the digital intermediate frequency value.

[0055] Specifically, in this embodiment, the calculation formula of the digital intermediate frequency value is as follows:

[0056] Among them, f0 is used to represent the required intermediate frequency, f s Used to indicate digital sampling rate, the intermediate frequency bit width is 12 bits.

[0057] The linear frequency modulation signal can be frequency-division multiplexed by adjusting the digital intermediate frequency. After the digital intermediate frequency value is calculated, it can be transmitted to the register 500 of each receiving chip through an interface such as SPI to change the configuration of the digital intermediate frequency. The mixer receives this configuration and moves the input signal to different positions to achieve frequency differentiation of different receiving chips.

[0058] In summary, the linear frequency modulation signal-based gateway system of the present invention can be set up to receive antennas without the need for a combiner, and the intermediate frequency output will not lose signal energy. The frequencies of each receiving chip can be distinguished by configuring the spreading factor and the digital intermediate frequency value to meet the usage requirements of different frequency bands. In addition, in actual application scenarios, multiple receiving chips can be made into a packaged module, which makes the frequency band selection more flexible.

[0059] The above description is only a preferred embodiment of the present invention and does not limit the implementation mode and protection scope of the present invention. For those skilled in the art, it should be aware that all solutions obtained by equivalent substitutions and obvious changes made using the content of this specification and illustrations should be included in the protection scope of the present invention.

Claims

1. A gateway system based on linear frequency modulation signal, characterized in that: It includes at least one group of receiving channels, each group of receiving channels includes multiple receiving chips, one of the receiving chips is connected to a receiving antenna and the other receiving chips respectively, and the receiving chip connected to the receiving antenna is used to distribute the linear frequency modulation signal received by the receiving antenna to the corresponding receiving chip for demodulation, so as to output multiple demodulated linear frequency modulation signals in different frequency bands.

2. The gateway system according to claim 1, characterized in that: Each of the receiving chips comprises an analog-to-digital converter and a digital demodulation module connected in sequence; The receiving chip connected to the receiving antenna also includes a signal distribution module, and the output of the signal distribution module is respectively connected to the input of the analog-to-digital converter of the receiving chip where the receiving chip is located and the input of the analog-to-digital converter of each of the remaining receiving chips, so as to send the linear frequency modulation signal received by the receiving antenna to the corresponding analog-to-digital converter for analog-to-digital conversion and then send it to the digital demodulation module for demodulation to obtain the demodulated linear frequency modulation number of the corresponding frequency band.

3. The gateway system according to claim 2, characterized in that: Each of the receiving chips is respectively associated with a corresponding preset spreading factor, and the signal distribution module includes: A storage unit, used for storing the association relationship between each of the preset spreading factors and each of the receiving chips; The first allocation unit is connected to the storage unit and is used to obtain the real-time spreading factor of the received linear frequency modulation signal and allocate the linear frequency modulation signal to the receiving chip associated with the preset spreading factor matching the real-time spreading factor.

4. The gateway system according to claim 2, characterized in that: The signal distribution module comprises: A monitoring unit, used for monitoring the current status of each receiving chip in real time; A second allocation unit is connected to the monitoring unit, and is used to obtain the real-time spreading factor of the received linear frequency modulation signal, and configure the real-time spreading factor to any receiving chip whose current state is idle, and then allocate the linear frequency modulation signal to the receiving chip configured with the real-time spreading factor.

5. The gateway system according to claim 4, characterized in that: Each of the receiving chips is provided with a plurality of bus pins, and the signal distribution module is correspondingly connected to the remaining receiving chips through each of the bus pins to configure the real-time spreading factor into each of the receiving chips.

6. The gateway system according to claim 5, characterized in that: Each of the bus pins is a SPI bus pin or an IIC bus pin.

7. The gateway system according to claim 2, characterized in that: Each of the receiving chips also includes a radio frequency module and an analog filter connected in sequence; For the receiving chip connected to the receiving antenna, the radio frequency module thereof is connected to the receiving antenna, and the output of the analog filter is connected to the analog-to-digital converter thereof through the signal distribution module; For the remaining receiving chips, the output of the analog filter is connected to its own analog-to-digital converter, and the RF module and the analog filter are not working.

8. The gateway system according to claim 2, characterized in that: The digital demodulation module comprises a mixer, a digital filter and a demodulator which are connected in sequence, and the input of the mixer is connected to the output of the corresponding analog-to-digital converter.

9. The gateway system according to claim 8, characterized in that: Each receiving chip is also provided with a register connected to the mixer and used to store a pre-configured digital intermediate frequency value; The mixer is used to perform mixing processing on the digital linear frequency modulation signal obtained by the analog-to-digital converter according to the digital intermediate frequency value.

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