KR100779743B1 - Apparatus and method for diversity of broadcasting service mobile terminal - Google Patents

Abstract

The diversity receiver of a broadcast receiving terminal according to the present invention includes a first antenna for receiving a mobile communication signal and a gap filler signal, a second antenna for receiving a satellite broadcast signal, and a signal received at the first and second antennas. The RF unit converts the signal into a lower frequency signal, and a signal restoring module for restoring an audio signal and a video signal from the converted signal. In the diversity receiver according to the present invention, a circularly polarized antenna having excellent polarization characteristics is manufactured and built in a patch shape, thereby miniaturizing the broadcast receiving mobile terminal. In addition, it solves the problem of the conventional broadcast receiving portable terminal to attach an external antenna each time a broadcast is received. In addition, the diversity receiver according to the present invention has excellent polarization characteristics of circular polarization, and greatly improves the reception effect of the diversity branch due to the suppression of the echo reflected wave reception. In addition, spatial polarization diversity using circular polarization eliminates a reduction in reception sensitivity generated in a multipath fading environment. In addition, by using only two antennas, compared to the conventional portable terminal, which had to use three antennas (including an external DMB antenna), it is easy to manufacture, has an economic effect due to reduced component cost, and has an advantage of easy portability.

 DMB, satellite DMB, polarization diversity

Description

Diversity receiver and method for broadcasting receiver terminal {APPARATUS AND METHOD FOR DIVERSITY OF BROADCASTING SERVICE MOBILE TERMINAL}

1 is a block diagram of a typical satellite DMB system.

2 is a block diagram of a diversity receiver according to an embodiment of the present invention.

*** Explanation of symbols for main parts of drawing ***

10: terrestrial broadcasting center 20: satellite

30: gap filler 40: terminal

110: dual band antenna 120: DMB antenna

130: RF part 134: first RF chip

138: second RF chip 140: DMB AV module

The present invention relates to a portable terminal, and more particularly, to a portable terminal having a satellite broadcasting reception function.

Analog broadcasting currently in service was originally developed for fixed reception, so when the receiver is walking or driving a vehicle, the reception sound quality deteriorates and requires high output and a wide frequency band.

In order to solve this problem, the standardization and commercialization of digital audio broadcasting is currently in progress in various regions of the world, and in Europe, which adopts Eureka-147 as the digital audio broadcasting standard, Digital Audio Broadcasting (DAB), USA Is used as DAR (Digital Audio Radio) in Canada, DRB (Digital Radio Broadcasting) in Canada, and DSR (Digital Sound Broadcasting) in ITU-R.In Korea, it is managed by the Ministry of Information and Communication. It is used as the name (Digital Multimedia Broadcasting).

As such, digital audio broadcasting, which is being standardized and commercialized, has been developed for the next generation broadcasting, and is capable of receiving CD-level sound quality in a vehicle that runs at high speed even when transmitted at a low power due to strong radio wave environment and noise in urban areas. In addition, the concept of radio broadcasting has been expanded from the existing "listening broadcast" to "looking and listening broadcast". In addition to music broadcasting, various multimedia information such as news, traffic information, weather information, geographic location information, video information, etc. can be converted into text and graphics. Can transmit

DMB, or digital multimedia broadcasting, named by Korea's telecommunications industry, is capable of transmitting 1.5Mbit / sec of data to high-quality CD sound quality, text, graphics, and moving images beyond the conventional AM and FM radio formats as voice broadcasting becomes digital. It is the next generation broadcasting technology that provides various data services, two-way interactivity, and excellent mobile reception quality.

Korean communication terminal manufacturers are currently developing or already developing and selling mobile terminals using DMB technology to consumers.

In the case of satellite DMB systems that service satellite broadcasting, the satellite transmits the broadcast signal directly to the terrestrial terminal or other receiver through circular polarization, or the satellite broadcast signal is transmitted through the ground gap filler or relay station. Send indirectly to In particular, in a shaded area where satellite signals cannot reach, a broadcast signal is transmitted to the terminal using a gap filler.

1 shows a configuration of a general satellite DMB system.

In the general satellite DMB system, when the broadcasting center 10 of the terrestrial broadcasting center launches various multimedia contents to the satellite through the Ku band frequency, the satellite 20 transmits the multimedia content to the terminal 40 at the S band frequency (2.630 to 2.655 GHz). The broadcast service is performed by transmitting directly to the subscribers on the ground through the G-band (Gap filler, 30) in the Ku-band back to the S-band.

The gap filler 30 is a kind of terrestrial repeater that transmits a broadcast signal to enable reception even in a shaded area where it is difficult to receive a broadcast service directly from a satellite. The signal of the satellite DMB system is sensitive to changes in the wireless environment or the atmosphere, and is also affected by the minute changes in the wireless environment or the atmosphere change. Gap fillers are installed in the shadow area of satellite DMB system to compensate for this problem, but there are many difficulties in installing the gap fillers economically and temporally (or spatially).

In the terminal 40, a pole antenna used for a mobile phone is generally used without using a parabolic antenna required for reception of satellite broadcasting.

The diversity receiver of a conventional mobile terminal receives a DMB signal using two antennas spaced apart from each other. One of them is a dual band antenna for CDMA and satellite DMB, and the other is a gap filler dedicated antenna. Thus, the two antennas are separated from each other within a certain distance to obtain only a spatial effect.

In addition, in order to receive satellite signals directly, an external satellite antenna had to be attached to the mobile terminal. In this case, since the signal path of the gap filler antenna is off, the satellite signal is received only through the satellite dedicated antenna path. Therefore, the conventional method is not only inconvenient for the subscriber to carry the external antenna to receive the satellite signal directly, but also has the inconvenience of having to detach the satellite antenna every time.

The present invention is to solve the problems described above, the object is,

Disclosed is a diversity receiver and method for a broadcast receiving terminal that performs spatial polarization diversity by embedding a circular polarization antenna in a patch form.

In order to achieve the above object, the diversity receiver of a mobile terminal according to the present invention

A first antenna for receiving a mobile communication signal and a gap filler signal, a second antenna for receiving a satellite broadcast signal, an RF unit for converting signals received at the first and second antennas into an IQ signal, and the IQ signal; And a signal restoring module for restoring the audio and video signals.

Preferably, the second antenna is a circularly polarized patch antenna.

Preferably, the RF unit includes a first RF chip converting the signal received by the first antenna into an IQ signal, and a second RF chip converting the signal received by the second antenna into an IQ signal. .

Preferably, the second antenna is characterized in that directly receiving a circular polarization of a satellite signal.

In order to achieve the above object, the diversity receiving method of the mobile terminal according to the present invention

Receiving a mobile communication signal and a gap filler signal through a first antenna; receiving a satellite broadcast signal through a second antenna; converting signals received at the first and second antennas into IQ; And restoring an audio signal and a video signal from the IQ signal.

The present invention has been made in order to apply a spatially polarized diversity method to a diversity receiver of a mobile terminal in order to improve reception sensitivity.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

2 is a block diagram of a diversity receiver according to an embodiment of the present invention.

As shown in Figure 2, the diversity receiver according to the present invention

A dual band antenna 110 capable of receiving both a Code Division Multiple Access (CDMA) signal and a gap filler signal, a DMB antenna 120 receiving satellite DMB signals, the dual band antenna 110 and a DMB antenna ( An RF unit 130 for converting the signal received by the 120 into an in-phase quadrature-phase (IQ) signal and an IQ signal from the RF unit 130 to receive an audio signal and a video signal. It is characterized in that it comprises a satellite DMB AV (AV) module 140 to restore the.

The RF unit 130 converts a signal received by the dual band antenna 110 into an IQ signal and a second RF chip 134 and a second signal converting the signal received by the DMB antenna 120 into an IQ signal. RF chip 138.

As the DMB antenna 120, the present invention employs a circularly polarized patch antenna capable of directly receiving a circularly polarized wave that is a satellite signal. Circularly polarized patch antennas are so small that they can be embedded in portable terminals.

The dual band antenna 110 and the DMB antenna 120 embedded in the portable terminal are designed to maintain the separation distance at regular intervals.

Referring to Figure 2, the operation of the diversity receiver according to the present invention will be described in detail as follows.

As shown in FIG. 2, the present invention configures a spatial diversity branch inside the portable terminal using the two antennas 110 and 120. FIG.

In a line of sight (LOS) environment where satellites are visible, or in outlying areas (eg, at sea) where gap fillers are not installed, the diversity branch according to the invention maintains a constant separation distance. Two antennas, that is, the dual band antenna 110, which is a CDMA and satellite DMB combined antenna, and a DMB antenna 120 capable of receiving satellite signals, receive a broadcast signal and receive the received signal from the first RF chip. 134 and the second RF chip 138, respectively. The IQ signals generated by the two RF chips 134 and 138 are transferred to the satellite DMB AV module 140 to restore the audio signal and the video signal.

Therefore, in the present invention, when a subscriber is located in a field of view (LOS) environment or an area where a gap filler is not installed, a broadcast signal of a satellite via the DMB antenna 120 employing a circularly polarized patch antenna is provided. By directly receiving the spatial diversity effect can be obtained.

In addition, in the case of receiving a signal of a CDMA base station, even if the strength of the received signal is weak, the present invention can receive the terminal through spatial polarization diversity using two branches of the dual band antenna 110 and the DMB antenna 120. Increase sensitivity

On the other hand, in a city area where a satellite is not visible (Non Line of Sight, NLOS) environment or a gap filler (Gap filler) is installed, the diversity receiver according to the present invention is the dual band antenna 110 And through the DMB antenna 120, diversity is performed by receiving a broadcast signal and extracting a vertical or horizontal polarization component from the received signal. This not only achieves a spatial effect, but also polarization diversity effect due to the use of vertical or horizontal polarization characteristics with existing antennas.

In general, the CDMA and the gap filler antenna generally employ an antenna having vertical polarization characteristics. When the circular polarization antenna is used, the polarization characteristics of the circular polarization are excellent to resist fading and to suppress the reception of reflected echoes. Due to its reception characteristics are good. In the case of the present invention, the reception sensitivity is about 3 dB or more compared to the vertical horizontal polarization diversity branch. In the case of spatial diversity, the present invention also improves the reception sensitivity by about 3 dB.

The effects of the present invention are as follows.

In the diversity receiver according to the present invention, a circularly polarized antenna having excellent polarization characteristics is manufactured and built in a patch shape, thereby miniaturizing the broadcast receiving mobile terminal. In addition, it solves the problem of the conventional broadcast receiving portable terminal to attach an external antenna each time a broadcast is received. In addition, the diversity receiver according to the present invention has excellent polarization characteristics of circular polarization, and greatly improves the reception effect of the diversity branch due to the suppression of the echo reflected wave reception.

In addition, spatial polarization diversity using circular polarization eliminates a reduction in reception sensitivity generated in a multipath fading environment. In addition, by using only two antennas, compared to the conventional portable terminal, which had to use three antennas (including an external DMB antenna), it is easy to manufacture, has an economic effect due to reduced component cost, and has the advantage of being portable.

Although the present invention has been described with reference to the embodiments illustrated in the drawings, this is merely exemplary, and it will be understood by those skilled in the art that various modifications and equivalent other embodiments are possible. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

Claims (11)

A first antenna for receiving a mobile communication signal and a gap filler signal; A second antenna for receiving a satellite broadcast signal; An RF unit converting the signals received at the first and second antennas into IQ signals; And a signal restoration module for restoring an audio signal and a video signal from the IQ signal. The second antenna is a diversity receiver of a portable terminal, characterized in that the circularly polarized patch antenna. delete According to claim 1, wherein the RF portion A first RF chip converting the signal received by the first antenna into an IQ signal; And a second RF chip converting the signal received by the second antenna into an IQ signal. Claim 4 was abandoned when the registration fee was paid. The method of claim 1, wherein the mobile communication signal A diversity receiver of a portable terminal, which is a code division multiple access (CDMA) signal. delete Claim 6 was abandoned when the registration fee was paid. The method of claim 1, wherein the second antenna A diversity receiver of a portable terminal, characterized in that it directly receives a circular polarization signal which is a satellite signal. Receiving a mobile communication signal and a gap filler signal through the first antenna; Receiving a satellite broadcast signal through a second antenna which is a circular polarization patch antenna; Converting the signals received at the first and second antennas into IQ signals; And a method for recovering an audio signal and a video signal from the IQ signal. delete Claim 9 was abandoned upon payment of a set-up fee. The method of claim 7, wherein the mobile communication signal is A diversity reception method of a portable terminal, characterized in that it is a Code Division Multiple Access (CDMA) signal. delete Claim 11 was abandoned upon payment of a setup registration fee. The method of claim 7, wherein the second antenna A diversity reception method of a portable terminal, characterized in that it directly receives a circular polarization signal which is a satellite signal.

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