Multi-channel W-waveband chip and radio frequency module thereof

Abstract

The invention provides a multichannel W-band chip and a radio frequency module thereof, the multichannel W-band chip comprises a control system, a local oscillator module, a frequency multiplier, a power divider, a W-band transmitting link and a W-band receiving link, the control system controls the transceiving state of a radio frequency channel, the local oscillator module generates a local oscillator signal and performs chip cascading, the frequency multiplier is used for generating a W-band signal, and the W-band receiving link is used for receiving the W-band signal. The power divider is used for dividing the signals into multiple paths of internal W-band signals and transmitting the signals to the W-band transmitting link or the W-band receiving link, the W-band transmitting link performs phase shift amplification on the internal W-band signals and then outputs the signals to the radio frequency channel for transmission, and the W-band receiving link receives external W-band signals entering from the radio frequency channel and performs frequency mixing with the internal W-band signals; and the generated intermediate-frequency signal is output to an external signal processing part after being filtered and amplified. According to the invention, a multi-channel W-band signal receiving and transmitting function can be realized, and multi-chip cascade connection is supported, so that more receiving and transmitting radio frequency channels can be integrated, and increasingly complicated design requirements of a radar antenna array are met.

Description

Technical Field

[0001] The present invention relates to the technical field of millimeter wave integrated circuits, and in particular to a multi-channel W-band chip and a radio frequency module thereof. Background Art

[0002] With the development of the integrated circuit industry, millimeter wave chips are crucial in the integrated circuit industry, especially in the fields of wireless communications, radar systems, sensor technology, etc. However, the existing research results related to W-band millimeter wave chips have the following limitations:

[0003] First, existing millimeter-wave chips are mainly concentrated in the low-frequency band of the W band where the W band and E band overlap. There is less related research in the higher-frequency band of the W band, and most of the results are concentrated on a single module circuit or a single antenna, and the technology is not yet mature.

[0004] Second, the current W-band chip solutions are mostly focused on complete system packaging modules of active phased array AiP (packaged antenna), but the application scenarios of millimeter-wave radars are becoming increasingly complex, requiring more flexible and diverse antenna array designs.

[0005] Third, the existing W-band chips have a low level of integration, integrating only a single-channel module or only 2×2 transceiver channels, which cannot meet the design requirements of multi-channel transceiver of millimeter-wave radar, limiting its system performance.

[0006] Fourth, the W-band signal transmission loss is relatively high. For traditional microstrip antenna solutions, the gain is low and cannot meet the needs of long-distance power detection.

[0007] Therefore, there is an urgent need for a multi-channel W-band chip that can realize multi-channel W-band signal transceiver functions, support multi-chip cascading, and meet the increasingly complex radar antenna array design requirements. Summary of the invention

[0008] Based on this, it is necessary to provide a multi-channel W-band chip and its RF module to address the above technical problems.

[0009] A multi-channel W-band chip and a radio frequency module thereof, comprising: a local oscillator module, a frequency multiplier, a power divider, a W-band transmission link and a W-band reception link connected to a control system; the local oscillator module is connected to the frequency multiplier, the frequency multiplier is connected to the power divider, and the power divider is connected to the W-band transmission link or the W-band reception link; the control system is used to control the transceiver state of the radio frequency channel; the local oscillator module is used to generate a local oscillator signal and perform chip cascading; the frequency multiplier is used to receive the local oscillator signal and multiply the local oscillator signal to obtain a W-band signal; the power divider is used to divide the W-band signal into multiple internal W-band signals and transmit them to the W-band transmission link or the W-band reception link; the W-band transmission link is used to phase-shift and amplify the internal W-band signal and then output it to the radio frequency channel for transmission; the W-band reception link is used to receive an external W-band signal entering from the radio frequency channel, mix it with the internal W-band signal, and output the intermediate frequency signal generated after mixing to an external signal processing part after filtering and amplification.

[0010] In one embodiment, the local oscillator module includes a phase-locked loop, a frequency synthesizer and a chip cascade control circuit, the phase-locked loop is connected to the frequency synthesizer, the frequency synthesizer is connected to the chip cascade control circuit, and the chip cascade control circuit is connected to the frequency multiplier; the phase-locked loop and the frequency synthesizer are used to generate a local oscillator signal according to an external crystal oscillator signal, and the chip cascade control circuit is used to perform clock self-calibration on the local oscillator signal and synchronize it with the cascade chip.

[0011] In one of the embodiments, the frequency multiplier is a 6-fold frequency multiplier.

[0012] In one embodiment, the power divider is a one-to-four power divider.

[0013] In one embodiment, the W-band transmission link includes a phase shifter and a power amplifier, the phase shifter is connected to the power amplifier, the phase shifter is connected to the second transceiver switch, and is used to phase shift the internal W-band signal, and the power amplifier is connected to the first transceiver switch, and is used to amplify the phase-shifted W-band signal and transmit it to the RF path.

[0014] In one embodiment, the phase shift range of the phase shifter is 0-360°, and the phase shift step is 5.652°.

[0015] In one embodiment, the W-band receiving link includes a low-noise amplifier, a mixer, a high-pass filter, a power amplifier and a low-pass filter. The low-noise amplifier is connected to the first transceiver switch and is used to receive an external W-band signal entering from a radio frequency channel. The mixer is connected to the second transceiver switch and is used to mix the external W-band signal with the internal W-band signal to generate an intermediate frequency signal. The high-pass filter is used to perform high-pass filtering on the intermediate frequency signal. The second power amplifier is used to amplify the intermediate frequency signal after high-pass filtering. The low-pass filter is used to perform low-pass filtering on the amplified intermediate frequency signal and output it to an external signal processing part.

[0016] In one of the embodiments, it also includes: a temperature control module and a power detection module, both of which are connected to the control system, the temperature control module is used to control the chip temperature, and the power detection is used to detect the working power of the chip.

[0017] In one of the embodiments, it also includes a transceiver antenna, and the transceiver antenna is a 3D waveguide antenna.

[0018] Compared with the prior art, the advantages and beneficial effects of the present invention are: a frequency multiplier is connected to a W-band transmitting link or a W-band receiving link through a local oscillator module, the frequency multiplier is connected to a power divider, the power divider is connected to a W-band transmitting link or a W-band receiving link, a control system is used to control the transceiver state of a radio frequency channel, the local oscillator module is used to generate a local oscillator signal and perform chip cascading, the frequency multiplier is used to receive the local oscillator signal and perform multiple processing to obtain a W-band signal, the power divider is used to divide the W-band signal into multiple internal W-band signals, and transmit them to a W-band transmitting link or a W-band receiving link, the W-band transmitting link amplifies the internal W-band phase shift and outputs it to the radio frequency channel for transmission, the W-band receiving link receives the external W-band signal entering from the radio frequency channel and mixes it with the internal W-band signal, and outputs the intermediate frequency signal generated after mixing to an external signal processing part after filtering and amplification, so as to realize the multi-channel W-band signal transceiver function, support multi-chip cascading, thereby integrating more transceiver radio frequency channels to meet the increasingly complex radar antenna array design requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 The figure is a principle block diagram of a multi-channel W-band chip and its radio frequency module in one embodiment.

[0020] Figure 2 The figure is a circuit schematic diagram of a multi-channel W-band chip and a radio frequency module thereof in one embodiment.

[0021] FIG3 is a schematic diagram of a W-band multi-channel module in one embodiment, wherein (a) is a schematic diagram of a single-chip module; and (b) is a schematic diagram of a multi-chip cascade module.

[0022] FIG. 4 is a schematic diagram of a transfer structure based on WLCSP packaging in one embodiment, wherein (a) is a main viewing angle and (b) is a top-down viewing angle.

[0023] Figure 5 FIG. 1 is a schematic diagram of a performance simulation of a transfer structure based on WLCSP packaging in an embodiment.

[0024] FIG6 is a schematic diagram of a gold wire bonding structure in an embodiment, wherein (a) is a top view and (b) is a side view.

[0025] Figure 7 Schematic diagram of performance simulation of a gold wire bonding structure in one embodiment.

[0026] FIG8 is a schematic diagram of a LoP direct-connect waveguide structure in one embodiment, wherein (a) is a main viewing angle and (b) is a side viewing angle. DETAILED DESCRIPTION

[0027] Before describing the specific embodiments of the present invention, the overall concept of the present invention is described as follows:

[0028] The present invention is mainly developed based on the millimeter wave integrated circuit process. Currently, there is a lack of W-band chips in the millimeter wave radar field, and they cannot meet the complex application scenarios of millimeter wave radars.

[0029] Therefore, the present invention proposes a multi-channel W-band chip and its radio frequency module, which are connected to a frequency multiplier through a local oscillator module, which is connected to a power divider, which is connected to a W-band transmitting link or a W-band receiving link, and a control system is used to control the transceiver state of the radio frequency channel. The local oscillator module is used to generate a local oscillator signal and perform chip cascading, the frequency multiplier is used to receive the local oscillator signal and multiply the frequency to obtain a W-band signal, the power divider is used to divide the W-band signal into multiple internal W-band signals, and transmit them to the W-band transmitting link or the W-band receiving link. The W-band transmitting link amplifies the internal W-band phase shift and outputs it to the radio frequency channel for transmission, the W-band receiving link receives the external W-band signal entering from the radio frequency channel and mixes it with the internal W-band signal, and outputs the intermediate frequency signal generated after mixing to the external signal processing part after filtering and amplification, which can realize the multi-channel W-band signal transceiver function and support multi-chip cascading, so that more transceiver radio frequency channels can be integrated to meet the increasingly complex radar antenna array design requirements.

[0030] After introducing the overall concept of the present invention, in order to make the purpose, technical solution and advantages of the present invention more clear, the present invention is further described in detail by specific implementation methods in combination with the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0031] In one embodiment, Figure 1 As shown, a multi-channel W-band chip and its radio frequency module are provided, including: a local oscillator module 20 connected to a control system 10, a frequency multiplier 30, a power divider 40, a W-band transmission link 50 and a W-band reception link 60, the local oscillator module 20 is connected to the frequency multiplier 30, the frequency multiplier 30 is connected to the power divider 40, the power divider 40 is connected to the W-band transmission link 50 or the W-band reception link 60; the control system 10 is used to control the transceiver state of the radio frequency channel; the local oscillator module 20 is used to generate a local oscillator signal and perform chip cascading; the frequency multiplier 30 is used to The power divider 40 is used to divide the W-band signal into multiple internal W-band signals and transmit them to the W-band transmission link 50 or the W-band receiving link 60; the W-band transmission link 50 is used to phase-shift and amplify the internal W-band signal and then output it to the RF channel for transmission; the W-band receiving link 60 is used to receive the external W-band signal entering from the RF channel and mix it with the internal W-band signal, and then filter and amplify the intermediate frequency signal generated after mixing and output it to the external signal processing part.

[0032] In this embodiment, the frequency multiplier 30 is connected to the local oscillator module 20, the frequency multiplier 30 is connected to the power divider 40, the power divider 40 is connected to the W-band transmission link 50 or the W-band reception link 60, and the control system 10 is used to control the transceiver state of the RF channel. The local oscillator module 20 is used to generate a local oscillator signal and perform chip cascading. The frequency multiplier 30 is used to receive the local oscillator signal and multiply the frequency to obtain the W-band signal. The power divider 40 is used to divide the W-band signal into multiple internal W-band signals and transmit them to the W-band transmission link 50 or the W-band reception link 60. The W-band transmission link 50 amplifies the internal W-band phase shift and outputs it to the RF channel for transmission. The W-band reception link 60 receives the external W-band signal entering from the RF channel and mixes it with the internal W-band signal. The intermediate frequency signal generated after mixing is filtered and amplified and then output to the external signal processing part. The multi-channel W-band signal transceiver function can be realized, and multi-chip cascading is supported, so that more transceiver RF channels can be integrated to meet the increasingly complex radar antenna array design requirements.

[0033] In one embodiment, Figure 2 As shown, the control system 10 includes a first transceiver switch and a second transceiver switch, wherein one end of the first transceiver switch is connected to the RF channel, and the other end is connected to the W-band transmission link or the W-band reception link, for outputting W-band signals or receiving external W-band signals; one end of the second transceiver switch is connected to the frequency multiplier, and the other end is connected to the W-band transmission link or the W-band reception link, for transmitting internal W-band signals.

[0034] Specifically, the control system 10 can control the first transceiver switch T / R Switch1 and the second transceiver switch T / RSwitch2. The first transceiver switch is connected to the RF channel and is used to control the output W signal or receive the external W-band signal. The second transceiver switch is connected to the frequency multiplier and is used to control the transmission of the internal W-band signal to transmit the external W-band signal and the internal W-band signal to the W-band transmission link 50 or the W-band reception link 60.

[0035] In one embodiment, Figure 2 As shown, the local oscillator module 20 includes a phase-locked loop, a frequency synthesizer and a chip cascade control circuit. The phase-locked loop is connected to the frequency synthesizer, the frequency synthesizer is connected to the chip cascade control circuit, and the chip cascade control circuit is connected to the frequency multiplier; the phase-locked loop and the frequency synthesizer are used to generate a local oscillator signal according to an external crystal oscillator signal, and the chip cascade control circuit is used to perform clock self-calibration on the local oscillator signal and synchronize with the cascade chip.

[0036] Specifically, the local oscillator module 10 includes a phase-locked loop PLL, a frequency synthesizer RF synthesizer and a chip cascade control circuit. The signal generated by the external crystal oscillator XTAL passes through the built-in phase-locked loop and the frequency synthesizer in turn to generate a stable and high-quality local oscillator signal LO, which also serves as a clock signal; the chip cascade control circuit includes a multi-way selection switch for synchronization with other cascade chips and clock self-calibration. The chip cascade control circuit can be used to achieve cascading with multiple W-band chips to achieve multi-channel transmission and reception, making the millimeter-wave radar antenna array design more flexible.

[0037] In one embodiment, the frequency multiplier 30 is a 6-times frequency multiplier.

[0038] Specifically, the local oscillator module 20 generates a local oscillator signal and transmits it to the frequency multiplier 30, and obtains a W-band signal after being multiplied by 6.

[0039] In one embodiment, the W-band transmission link 50 includes a phase shifter and a power amplifier, the phase shifter is connected to the power amplifier, the phase shifter is connected to the second transceiver switch, and is used to phase shift the internal W-band signal, and the power amplifier is connected to the first transceiver switch, and is used to amplify the phase-shifted W-band signal and transmit it to the RF path.

[0040] Specifically, the W-band transmission chain 50 includes a phase shifter and power amplifier PA1, phase shifter It is connected to the second transceiver switch T / R Switch2 to receive the internal W-band signal, and transmits it to the power amplifier PA1 after phase shifting. The power amplifier PA1 is connected to the first transceiver switch T / R Switch1, so that it can amplify the internal W-band signal after phase shifting, and transmit it to the RF path RF1~4 through the first transceiver switch T / R Switch1 for signal transmission.

[0041] In one embodiment, the phase shift range of the phase shifter is 0-360°, and the phase shift step is 5.652°.

[0042] Specifically, the phase shifter A 6-phase shifter is used. In order to cover all possible phase changes, the phase shifter in the link adopts a phase shift range of 0 to 360° and a phase shift step of 5.652°, so that the phase shifter can adjust the phase of the internal W-band signal as needed to achieve different functions.

[0043] In one embodiment, the W-band receiving link 60 includes a low-noise amplifier, a mixer, a high-pass filter, a power amplifier and a low-pass filter. The low-noise amplifier is connected to the first transceiver switch and is used to receive an external W-band signal entering from the radio frequency channel. The mixer is connected to the second transceiver switch and is used to mix the received external W-band signal with the internal W-band signal to generate an intermediate frequency signal; the high-pass filter is used to high-pass filter the intermediate frequency signal, the second power amplifier is used to amplify the intermediate frequency signal after the high-pass filtering, and the low-pass filter is used to low-pass filter the amplified intermediate frequency signal and output it to the external signal processing part.

[0044] Specifically, the W-band receiving link 60 includes a low noise amplifier LNA, a mixer Mixer, a high pass filter HPF, a second power amplifier PA2 and a low pass filter LPH. The low noise amplifier LNA is connected to the first transceiver switch T / R Switch1 to receive the external W-band signal entering from the radio frequency channel. The mixer Mixer is connected to the second transceiver switch T / R Switch2 and the low noise amplifier LNA to obtain the internal and external W-band signals, and the two are mixed to generate an intermediate frequency signal; the intermediate frequency signal is high-pass filtered by a high-pass filter, and the high-pass filter is used to balance the echo signal strength of targets at different distances received outside the radar. The second power amplifier PA2 amplifies the filtered signal, and finally the low pass filter LPH is used to perform low pass filtering, and the obtained signal is transmitted to the external signal processing part.

[0045] In one embodiment, the chip and its radio frequency module further include: a temperature control module and a power detection module, and both the temperature control module and the power detection module are connected to the control system.

[0046] Specifically, the chip is also integrated with modules such as temperature control and power detection, and the control system 10 is used to control the integrated modules. The temperature control module is used to control the chip temperature, and the power detection is used to detect the working power of the chip.

[0047] In one embodiment, the chip and its radio frequency module further include: a transceiver antenna, which is a 3D waveguide antenna.

[0048] Specifically, the transmitting and receiving antennas can be selected according to the needs, for example, a 3D waveguide antenna is used. In this case, the RF channel is connected to the waveguide channel through a switching structure.

[0049] In one embodiment, as shown in FIG3 , it is a schematic diagram of a multi-channel module in the W band. Among them, (a) is a schematic diagram of a single-chip module, including a control system, a chip and a transceiver antenna, and the channel status is two transmit and two receive; (b) is a multi-chip cascade module, chip 1 is the master chip, and the remaining 2 to n chips are slave chips, and all cascade chips share the local oscillator signal derived from the master chip. The transceiver switch and amplifier power supply pins in the chip transceiver link are controlled by the control system. In addition to controlling the transceiver status of the channel, the amplifier power supply can also be turned off when the channel is not working as needed to reduce power consumption.

[0050] In one embodiment, the chip supports WLCSP (Wafer Level Chip Scale Packaging), gold wire bonding and LoP (Launch On Package) packaging.

[0051] The transfer structure from the W-band RF module chip pin part to the 3D waveguide antenna using WLCSP packaging is shown in Figure 4 (a) and (b). The W-band signal is transmitted to the microstrip line through the solder ball and coupled to the waveguide cavity through the radiation patch. The performance of the simulated W-band transfer structure is shown in Figure 4 (a) and (b). Figure 5 As shown, the waveguide specification is WR10. It has good transmission performance and an operating bandwidth of more than 8GHz in the W band.

[0052] The W-band RF module chip connection structure using the gold wire bonding solution is shown in Figure 6 (a) and (b). The bare chip is attached to the PCB through the IC carrier, and the RF channel related pins are connected to the microstrip line through gold wire bonding, and the W-band signal is transmitted to the 3D waveguide antenna through the transfer structure. Figure 7 This is the simulation result of the gold wire bonding structure performance. It has good transmission characteristics in the W band and can reduce the loss introduced by packaging.

[0053] The connection structure of the W-band RF module chip to the 3D waveguide antenna using the LoP packaged chip is shown in Figure 8 (a) and (b). The LoP package is inverted under the PCB board, and the W-band signal is directly transmitted to the waveguide channel through the PCB through-hole and fed into the 3D waveguide antenna without any switching structure. The main feed line is the waveguide channel, which greatly reduces the transmission loss of the W-band. At the same time, the ground solder balls around the package interface ensure the isolation between channels.

[0054] In summary, compared with the prior art, the present invention has the following advantages:

[0055] First, the W-band multi-channel chip provided by the present invention can realize the 4-channel W-band signal receiving and transmitting function, and can realize the switching of the receiving and transmitting channels or control in a fixed mode through external control, which can meet the application requirements of millimeter wave radar.

[0056] Second, the W-band multi-channel chip provided by the present invention is small in size, supports multi-chip cascading function, and is easy to be integrated into other systems. By cascading, more transceiver RF channels can be integrated to meet the increasingly complex radar antenna array design requirements.

[0057] Third, the radio frequency module of the W-band multi-channel chip provided by the present invention is not restricted to a certain fixed antenna form. Its universal waveguide interface can be connected to other modules and can also be compatible with antenna designs of various different indicators and structures.

[0058] Fourth, the W-band multi-channel chip provided by the present invention supports LoP packaging and can also use gold wire bonding, which effectively reduces the transmission loss of the overall RF module, effectively improves the radar power, and meets the needs of millimeter-wave radar long-distance detection.

[0059] The above contents are further detailed descriptions of the present invention in combination with specific implementation methods, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the concept of the present invention, which should be regarded as falling within the scope of protection of the present invention.

Claims

1. A multi-channel W-band chip and a radio frequency module thereof, characterized in that: include: A local oscillator module, a frequency multiplier, a power divider, a W-band transmission link and a W-band reception link connected to the control system; The local oscillator module is connected to a frequency multiplier, the frequency multiplier is connected to a power splitter, and the power splitter is connected to the W-band transmission link or the W-band reception link; The control system is used to control the transceiver state of the radio frequency channel; The local oscillator module is used to generate a local oscillator signal and perform chip cascading; The frequency multiplier is used to receive a local oscillator signal and multiply the frequency of the local oscillator signal to obtain a W-band signal; The power divider is used to divide the W-band signal into multiple internal W-band signals and transmit them to the W-band transmission link or the W-band reception link; The W-band transmission link is used to phase-shift and amplify the internal W-band signal and then output it to the radio frequency channel for transmission; The W-band receiving link is used to receive the external W-band signal entering through the RF channel and mix it with the internal W-band signal, and output the intermediate frequency signal generated after mixing to the external signal processing part after filtering and amplification.

2. The multi-channel W-band chip and the radio frequency module thereof according to claim 1, characterized in that: The control system includes a first transceiver switch and a second transceiver switch, one end of the first transceiver switch is connected to the RF channel, and the other end is connected to the W-band transmission link or the W-band reception link, and they are used together to control the working mode of the channel; one end of the second transceiver switch is connected to the frequency multiplier, and the other end is connected to the W-band transmission link or the W-band reception link, and is used to control the transmission of the internal W-band signal.

3. The multi-channel W-band chip and the RF module thereof according to claim 1, characterized in that: The local oscillator module includes a phase-locked loop, a frequency synthesizer and a chip cascade control circuit, the phase-locked loop is connected to the frequency synthesizer, the frequency synthesizer is connected to the chip cascade control circuit, and the chip cascade control circuit is connected to the frequency multiplier; the phase-locked loop and the frequency synthesizer are used to generate a local oscillator signal according to an external crystal oscillator signal, and the chip cascade control circuit uses the local oscillator signal to perform clock self-calibration and synchronization with the cascade chip.

4. The multi-channel W-band chip and the RF module thereof according to claim 1, characterized in that: The frequency multiplier is a 6-fold frequency multiplier.

5. The multi-channel W-band chip and the RF module thereof according to claim 1, characterized in that: The power divider is a one-to-four power divider.

6. The multi-channel W-band chip and the RF module thereof according to claim 2, characterized in that: The W-band transmission link includes a phase shifter and a power amplifier, the phase shifter is connected to the power amplifier, the phase shifter is connected to the second transceiver switch, and is used to shift the phase of the internal W-band signal, and the first power amplifier is connected to the first transceiver switch, and is used to amplify the phase-shifted W-band signal.

7. The multi-channel W-band chip and the radio frequency module thereof according to claim 6, characterized in that: The phase shift range of the phase shifter is 0-360°, and the phase shift step is 5.652°.

8. The multi-channel W-band chip and the radio frequency module thereof according to claim 2, characterized in that: The W-band receiving link includes a low-noise amplifier, a mixer, a high-pass filter, a power amplifier and a low-pass filter. The low-noise amplifier is connected to the first transceiver switch and is used to amplify the external W-band signal received by the radio frequency channel. The mixer is connected to the second transceiver switch and is used to mix the external W-band signal with the internal W-band signal to generate an intermediate frequency signal; the high-pass filter is used to perform high-pass filtering on the intermediate frequency signal, the power amplifier is used to amplify the intermediate frequency signal after high-pass filtering, and the low-pass filter is used to perform low-pass filtering on the amplified intermediate frequency signal and output it to the external signal processing part.

9. The multi-channel W-band chip and the radio frequency module thereof according to claim 1, characterized in that: Also includes: A temperature control module and a power detection module, both of which are connected to the control system.

10. The multi-channel W-band chip and the radio frequency module thereof according to claim 1, characterized in that: Also includes: The transceiver antenna is a 3D waveguide antenna.

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