JP2002246832A - Communication apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inexpensive and highly reliable communication apparatus and its system by which high-efficient and high-quality communication can be attained even in a millimeter wave band. SOLUTION: An IC circuit 101 is provided with a primary radiator 104 so that a low gain antenna can be built-in, and desired radiation directivity is realized by an antenna constituted of a dielectric lens 102 arranged outside the IC circuit 101. Thus, the generality of the IC circuit 101 can be sharply improved. Also, the antenna arranged outside is constituted of the dielectric lens 102 so that it is possible to establish both the sealing structure of a high frequency circuit and the satisfactory controllability of the radiation directivity, and to perform the scanning of the change of a gain value and the directivity.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication apparatus for transmitting and receiving electromagnetic waves using an antenna in a frequency band above the millimeter wave band.

[0002]

2. Description of the Related Art In recent years, demand for a high-speed and large-capacity transmission system has been rapidly increasing, and early realization of an inexpensive wireless communication system in a millimeter wave band capable of securing a wide frequency band is desired. Needless to say, it is important to reduce the loss of the antenna and the high-frequency circuit in order to realize high-rate, high-quality transmission / reception, but in general, as the frequency increases, the transmission line and the line connection / conversion unit are generated. In order to realize a transceiver that satisfies the above characteristics in the millimeter wave band, the transceiver must be configured so that the antenna, the transmission line in the high-frequency circuit, and the connection / conversion unit have low loss, because the loss becomes significant. Is indispensable.

In a conventional transceiver, a high-frequency circuit and an antenna are connected by a long transmission line, and in order to reduce a loss generated in the transmission line, the two are connected by using a line structure having a low transmission loss characteristic. Or it is necessary to shorten the line length. In addition, the most effective measure for reducing the loss in the connection / line conversion unit is to adopt a configuration with few such parts.

As one solution for achieving both of the above two points of low loss, a circuit configuration in which an antenna and a high-frequency circuit are integrated in one chip can be considered. Fortunately, the higher the frequency, the smaller the aperture area of the antenna required to achieve the same gain, so that in the millimeter-wave band, the above circuit configuration is specific as a feasible solution.

[0005] Based on this idea, for example, M. Sin
ger et. al, "Active SIMMWIC
-Antenna for Automotive A
applications "1997 IEEE MTT
-S International Microwav
e Symposium Digest, pp1265
As described in US Pat. No. -1268, an embodiment in which an antenna is integrated in a millimeter wave IC (hereinafter, MMIC) or a hybrid IC in a millimeter wave band (hereinafter, HIC) has been reported.

The above-mentioned conventional IC configuration will be described with reference to FIG. In FIG. 4, reference numeral 401 denotes a high-frequency circuit;
Is an antenna, and 403 is a high-resistance silicon substrate. In the cited conventional example, a high-frequency circuit 401 including a harmonic oscillator and a modulator and a microstrip antenna 402 are integrated in one high-resistance silicon substrate 403 to generate a harmonic signal of a signal from outside the IC. Then, the signal is transmitted by the antenna, the reflected wave from the object is received again by the antenna, and the difference signal between the two signals is output.

[0007]

In a wireless communication system, the directivity of a transmitting and receiving antenna is one of the important parameters that affect communication quality. Therefore, realization of various antenna directivities and gain values is required according to the specifications of the system. In general, the radiation directivity of an antenna is controlled by making the antenna structure an array structure or an aperture antenna structure. The gain value is determined by the size of the aperture surface, and the directivity is controlled by the electromagnetic field distribution on the aperture surface. Control.

By the way, in the conventional IC structure cited above, an increase in the antenna opening area causes an increase in the chip area, but this leads to an increase in the cost of the MMIC, and a problem of providing a low-cost communication device. Becomes In addition, in the configuration of the above-mentioned conventional example, a different antenna must be configured each time the use purpose / situation of the wireless communication system is different, so that the versatility of the MMIC and HIC is extremely reduced, and an increase in manufacturing cost is avoided. Instead, the cost of the entire communication system is increased.

Further, the high-frequency circuit is usually sealed in an airtight structure so that the circuit does not come into direct contact with the external environment in order to guarantee environmental resistance. However, antennas are designed to obtain characteristics under conditions close to free space,
With the conventional IC structure, it is difficult to achieve both the hermetic sealing structure and the antenna characteristics.

As described above, even if high efficiency and high quality in a high frequency band can be realized with the conventional configuration, it can be said that there is still a problem in providing a low-cost communication device and communication system. .

An object of the present invention is to solve the above-mentioned problems, and to provide an inexpensive, highly reliable, high-efficiency, high-quality communication apparatus / system even in the millimeter wave band.

[0012]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a first antenna, a low directivity antenna serving as a primary radiation source of electromagnetic waves to free space, together with a high frequency circuit and an integrated circuit. The radiation directivity of the entire communication device according to the purpose and situation of the communication system is integrated into an MMIC or HIC as a second antenna provided outside the chip, which is a large aperture antenna (an aperture antenna or an array antenna). ).

The first low directivity antenna is physically small, occupies a small area, and leads to a smaller chip. Also, the required directivity is realized by a second
It is not necessary to design and manufacture the first antenna in the chip according to the purpose of use, and the desired directivity can be realized only by replacing the second antenna. This greatly increases the versatility of the IC as compared with the configuration. Furthermore, the low directivity antenna is easier to design than the array antenna, has better consistency with the design, and can be expected to reduce the design cost.

Further, by using a dielectric lens as an antenna provided outside the chip as the second antenna, it is possible to easily realize an airtight structure surrounded by the dielectric lens and the housing. It is possible to achieve both environmental resistance of the circuit and good radiation directivity.

By using the configuration as described above,
In order to reduce the size and versatility of the antenna integrated IC and achieve compatibility between the environment resistance and the directivity of the device, we provide high-efficiency, high-quality communication devices and communication systems using them at low cost. can do.

[0016]

Embodiments of the present invention will be described below with reference to FIG.

(Embodiment) FIG. 1 is a schematic block diagram of a receiving apparatus according to the present invention. In FIG. 1, 101 is an IC circuit,
Reference numeral 104 denotes a primary radiator, and the high-frequency circuit and the primary radiator 104 as the first antenna are used as the same integrated circuit.
It is integrated on the C circuit 101. Reference numeral 102 denotes a dielectric lens, which corresponds to a second antenna. Reference numeral 103 denotes a signal processing circuit, and reference numeral 105 denotes a radio wave.

The operation of the thus configured receiving apparatus of the present invention will be described below. The propagated radio wave 105 is collected by the dielectric lens 102, guided into the IC circuit 101 by the primary radiator 104 located at the focal position, and converted into an intermediate frequency band signal. The converted signal is guided to the signal processing circuit 103 and converted into actual data and the like, and reproduction and processing of information are performed.

In the case of transmission, the data is converted into an intermediate processing conversion frequency (103), which is converted into an RF band by the IC circuit 101 and transmitted through the dielectric lens 102.

In the receiving apparatus of the present invention, the required radiation directivity is not generated by the antenna inside the IC circuit 101, but the primary radiator 104 inside the IC circuit 101 is simply a space outside the IC circuit 101. Only the function of radiating the electromagnetic wave to, and the radiation directivity required only by the dielectric lens 102 is obtained. Therefore, even when the specifications of the communication device are changed due to different usage conditions, if the entire circuit including the IC circuit 101 can cope with the change, the radiation directivity of the antenna can be easily changed by replacing the dielectric lens 102. Response is possible. Replacement is possible manually or with screws.

The dielectric lens 102 can be designed based on the radiation directivity of the primary radiator 104 and the radiation directivity (maximum gain value, beam half width, side lobe level) required by the system. Good radiation directivity can always be realized in a frequency region where the radiation directivity of 104 and the dielectric constant / permeability of the dielectric material forming the dielectric lens 102 do not extremely change.

Generally, the frequency dependence of the dielectric material used in the millimeter wave band is small, and the amount of change in the radiation directivity of the low gain antenna due to the frequency is small. Good radiation directivity can be ensured over a very wide band. Further, since the frequency characteristic of the absolute gain value of the entire antenna is defined only by the matching characteristic of the primary radiator 104, the band narrowing due to the increase in the number of antenna elements generally observed in the resonance type array antenna does not occur.

Further, the processing tolerance of the dielectric lens 102 is large compared to other antennas in the same frequency band, so that the antenna can be easily manufactured, and an antenna having a high aperture efficiency can be formed from the above-described good controllability of radiation directivity. In addition, it is easy to realize a high gain with a small aperture area as compared with a large aperture antenna of another system, and a communication device can be configured to be small.

The lens antenna structure has a dielectric lens 10
Since the hermetic structure surrounded by the communication device 2 and the communication device housing is naturally obtained, there is an advantage that hermetic sealing between the antenna and the high-frequency circuit, which is a problem when configuring a high-frequency circuit, can be easily realized. . When the replacement of the dielectric lens 102 occurs, a situation in which the hermetic sealing state is broken is encountered, but as shown in FIG.
If the dielectric thin film 301 is inserted between the two and a hermetic structure is realized by the dielectric thin film 301 and the housing 302, the hermetically sealed state is not broken by exchanging the dielectric lens 102.

By providing a mechanism for moving the dielectric lens 102, it becomes possible to easily change the spatial scanning and the gain value in the directional direction.
Can be controlled to some extent without replacing the. Therefore, by referring to FIG.
The advantage caused by the relative movement of the dielectric lens 102 with respect to the above will be described.

FIG. 2 is a schematic diagram showing a change in radiation characteristics due to the relative movement of the dielectric lens 102 and the primary radiator 104. For example, in the case of a system that requires a high-gain antenna, since the radiation directivity is sharp, to achieve good reception sensitivity, it is necessary to sufficiently position the antennas between communication devices. At this time, if the primary radiator 104 is positioned outside the focal plane of the lens by moving the dielectric lens 102 along the optical axis as shown in FIG. Alignment becomes easy.

In the final stage of fine adjustment, FIG.
As shown in (b), by moving the primary radiator 104 relatively within the focal plane of the dielectric lens 102, the adjustment of the maximum gain direction can be performed. Ancillary devices are simplified.

Returning to FIG. 1, the primary radiator 104 in FIG. 1 can use antennas having various structures.
Antenna structures that can be easily applied to the present invention are a microstrip antenna and a slot antenna. The microstrip antenna has a narrower band characteristic than the slot antenna, but can be realized with a very simple structure, is easily circularly polarized, and is useful for a system which is less affected by multiple reflected waves. In addition, the slot antenna has an advantage that it has excellent broadband characteristics and has good connectivity with a coplanar line which is relatively frequently used in a millimeter wave band high frequency circuit.

In the IC circuit 101, all components can be formed in a substrate using semiconductor technology. However, a semiconductor substrate such as GaAs that can be used in the millimeter wave band is very expensive, and even if it can be made small using the embodiment of the present invention, it still needs a large area as compared with a normal MMIC chip size. Therefore, a hybrid IC structure in which components are mounted on another inexpensive substrate such as silicon ceramic is considered to be appropriate.

A passive circuit element requiring a large area, such as a circuit wiring and a filter / antenna, is formed on an inexpensive substrate having good high-frequency characteristics such as ceramics, and an expensive substrate such as GaAs is formed using flip chip mounting technology. By mounting the passive elements that require the above, it is possible to provide the IC circuit 101 with low yield and low cost.

As described above, the low gain antenna as the primary radiator 104 is integrated into the IC circuit 101, and the radiation directivity required in the communication system is controlled by the dielectric lens 102 placed outside the IC circuit 101. By realizing, the same IC circuit 101 can be used in different situations, so that the manufacturing cost can be reduced, and a communication device / communication system can be manufactured at low cost while realizing high efficiency and high communication quality. To provide.

In the description of the embodiments of the present invention, the receiver has been described. However, it is needless to say that the present invention can be applied to all communication apparatuses which transmit and receive electromagnetic waves using an antenna in a frequency band equal to or higher than the millimeter wave band. .

Although the IC circuit 101 of the present invention has been described by taking as an example an apparatus configuration including only a high-frequency circuit, a structure in which a part or all of the signal processing circuits 103 are integrated in the same chip. Needless to say, the same effect can be obtained even with the above.

[0034]

As described above, according to the present invention, a low-gain antenna serving as a primary radiator is integrated inside a millimeter-wave band IC circuit, and radiation directivity required in a communication system is set outside the IC. By performing with the provided antenna,
Even in the millimeter wave band, it is possible to provide an inexpensive, highly reliable communication device and system with high efficiency and high quality.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a receiving device according to an embodiment of the present invention.

FIG. 2 is a schematic diagram showing a change in radiation characteristics due to a relative movement between a dielectric lens and a primary radiator.

FIG. 3 is a schematic view showing a method for hermetically sealing a high-frequency circuit according to the present invention.

FIG. 4 is a schematic configuration diagram of a conventional antenna integrated IC.

[Explanation of symbols]

 Reference Signs List 101 IC circuit 102 Dielectric lens 103 Signal processing circuit 104 Primary radiator 105 Radio wave

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H01Q 23/00 H01Q 23/00 (72) Inventor Mitsuo Makimoto 3-10 Higashi Mita, Tama-ku, Kawasaki City, Kanagawa Prefecture No. 1 Matsushita Giken Co., Ltd. F term (reference) 5J020 AA02 BB01 BB03 BC13 5J021 AB06 BA04 CA06 DA03 FA26 GA02 GA08 HA04 HA05 5J045 AA05 AA21 AB05 AB06 DA10 EA07 HA03 NA01 5J046 AA04 AA19 AB13 PA07

Claims (12)

[Claims] 1. A high-frequency circuit comprising a first antenna, a second antenna, and a high-frequency circuit, wherein the high-frequency circuit and the first antenna are formed on the same integrated circuit, the first antenna is a low-gain antenna, The communication device, wherein the second antenna is provided outside the integrated circuit, and obtains a desired radiation directivity by the second antenna. 2. The communication device according to claim 1, wherein the second antenna is a dielectric lens. 3. The communication device according to claim 1, wherein the integrated circuit has a hybrid integrated circuit structure including a substrate and a plurality of components. 4. The communication device according to claim 1, wherein the second antenna can be replaced. 5. The high-frequency circuit and the first antenna are configured inside the same integrated circuit, the first antenna is a low gain antenna, and the second antenna provided outside the integrated circuit is a dielectric lens. A communication device which realizes radiation directivity required by the second antenna, and wherein the second antenna and the first antenna are relatively movable. 6. The communication device according to claim 5, wherein the first antenna is relatively movable in a focal plane of the second antenna. 7. The communication device according to claim 5, wherein the first antenna is movable relatively in parallel to the optical axis of the second antenna. 8. The communication device according to claim 5, wherein the moving mechanism is for adjusting the position and angle of the communication device. 9. The communication device according to claim 5, wherein the moving mechanism is for adjusting the directivity of the second antenna. 10. The communication device according to claim 5, wherein airtight sealing of the high-frequency circuit is realized by a dielectric lens and a housing constituting the communication device. 11. A first antenna, a second antenna, an integrated circuit, a housing, and a dielectric thin film, wherein the first antenna is integrated in the integrated circuit, and a desired radiation directivity mainly depends on the radiation pattern. The high-frequency circuit generated by the second antenna and including the integrated circuit is sealed in an airtight structure including the housing and the dielectric thin film, and can be used in different situations by replacing the second antenna. A communication device, comprising: 12. A wireless communication device using the communication device according to claim 1. Description: