KR100560863B1 - Apparatus of dual bandwidth wireless subscriber for Portable Internet service and WLAN service - Google Patents

Abstract

The present invention relates to a dual bandwidth wireless terminal device.

The present invention provides a 5MHz band filter for portable Internet service; 20MHz band filter for WLAN service; A MAC / BB chip configured to interface with a user terminal to receive a set service band, perform CSMA / CA type MAC / control and baseband signal demodulation for IEEE 802.11a connection, and output frequency information of the service band; A switching signal combination unit generating a filter switching signal for setting a bandwidth corresponding to the frequency information; And a filter switching unit for connecting any one of a 5 MHz band filter and a 20 MHz band filter between the corresponding RF chip and the MAC / BB chip according to the filter switching signal.

According to the present invention, it is possible to provide both the portable Internet service of the 2.3GHz band and the wireless LAN service of the 2.4GHz band through an integrated dual bandwidth wireless terminal device. In addition, when the dual bandwidth wireless terminal device is manufactured, commercial chips of the conventional dual frequency wireless LAN cards of the 2.4 GHz band and the 5 GHz band, and core components are commonly used, can be manufactured at a lower cost.

2.3 GHz, Portable Internet Services, 2.4 GHz, Wireless LAN Services, Dual Bandwidth

Description

Apparatus of dual bandwidth wireless subscriber for Portable Internet service and WLAN service}

1 is a schematic diagram of a network for portable Internet service and WLAN service;

2 is an embodiment of a dual bandwidth wireless terminal device according to the present invention;

3 is a block diagram of a component for automatic bandwidth setting;

4 is an example of a process of selecting a band pass filter and setting a frequency according to the present invention;

5 illustrates an embodiment of an operation form of a dual bandwidth wireless terminal device according to the present invention.

* Explanation of symbols for main parts of the drawings

11: Server for providing service 12: IP network

13: network configuration device 14: mobile Internet base station

15: wireless LAN AP (access point) device 31: antenna

32: RF input / output unit 33: 2GHz band RF chip

34: switch section 35: 5 GHz termination

36: 5 GHz band RF chip 37: MAC / BB chip

38: filter switching unit 39: switching signal combination unit

The present invention relates to a dual-band wireless terminal device, and more particularly, to provide a dual-band wireless Internet service of 2.3 GHz band having a channel bandwidth of 5 MHz (or 10 MHz) or a wireless LAN service of a 2.4 GHz band having a channel bandwidth of 20 MHz. Bandwidth wireless terminal device.

Currently, the 2.4GHz band wireless LAN service is provided by wireline providers such as Dacom, Hanaro Telecom, and KT as part of high-speed Internet service. However, because of the low power and low gain antenna, the service range is very narrow, and ISM band (unlicensed band) of 2.400 to 2.4835 GHz that conforms to the IEEE 802.11b international standard is used. There are many problems in service commercialization. Therefore, the wireless LAN service of the 2.4 GHz band is limited to hotspots of indoor and narrow service ranges.

However, the WLAN system can be easily interworked with the Internet network and has advantages such as low device cost and high speed data transmission as a system specification according to the IEEE international standard. In addition, the specification of IEEE 802.11g is currently discussed for high speed data transmission. In the 5GHz band, low-cost wireless LAN products of the IEEE 802.11a standard are commercially available. The WLAN technology is a system having both the disadvantage of a narrow service range and the advantage of a low cost device complying with global standards.

The 2.3GHz band of the mobile Internet service is to be reassigned by the government to the conventional wireless local loop (WLL) frequency band. Accordingly, each service provider is studying which system is most effective in providing portable Internet service. One of the systems to be considered is a WLAN system method using the IEEE 802.11a standard used in the 5GHz band.

As described above, the wireless LAN service has a narrow service range and interference problems, and thus has a great difficulty in commercialization. However, if the new frequency band of 2.3 to 2.4 GHz is applied to the wireless LAN system, this problem can be solved. This is because the license frequency is allocated to guarantee no interference, and high power and high gain antennas can be used to extend the service range. In addition, the service bandwidth can be reduced to 5MHz to improve frequency usage efficiency and improve the system's lowest reception level. The portable Internet service using the wireless LAN method can overcome the disadvantages of the existing wireless LAN service and utilize the advantages of low-cost device cost and easy connection with the existing wired network.

The IEEE 802.11a specification provides speeds of 54 Mbps, and the modem chips were originally designed for use in the 5-6 GHz band, and the frequency band is set by the synthesizer of the 5 GHz band RF chip according to the IEEE 802.11a channel number. Input / output frequency (MHz) = channel number * 5 + 5000 That is, the frequency band is determined by the setting of the IEEE 802.11a channel number, such as 5.580 to 5.540 GHz for the channel numbers 116 to 128, and 5.725 to 5.825 GHz for the 145 to 165 band.

The conventional dual-mode wireless LAN terminal device that can be used for the wireless LAN service of the 2.4GHz / 5GHz ISM band by setting the frequency is set to channel numbers 116 to 128 and 2GHz by using a switch in front of the 5GHz band RF chip. Through the RF chip of the band, the center frequency can be transmitted and received at 2.412 ~ 2.472 GHz, and elsewhere, it can be used in the 5GHz band. In addition, RF input / output units (transceiver amplifiers and filters, etc.) in the 5 GHz band and the 2.4 GHz band are separately configured.

The current technology is developing terminal cards of dual frequency bands for IEEE standards of 2.4GHz band and 5GHz band, but as described above, mobile Internet service and wireless LAN service have different service frequency bands and different service bandwidths. Therefore, there is a need for a technology that converts this automatically.

Accordingly, the present invention is proposed to meet the above needs, and automatically converts the service bandwidth according to the service frequency band, so that the wireless LAN service and the 2.3GHz band of 2.4GHz band, which are activated mainly for hotspots in indoor and narrow areas. An object of the present invention is to provide an integrated dual bandwidth wireless terminal device capable of selectively using a portable Internet service.

In order to achieve the above object, the dual-bandwidth wireless terminal device according to the present invention includes a band-pass filter of 5MHz, which is a bandwidth for portable Internet service; A bandpass filter of 20MHz, which is a bandwidth for WLAN service; It interfaces with various terminals such as personal computer (PC), notebook, personal digital assistant (PDA), etc. to receive the set service band from the terminal, and modulates and demodulates the CSMA / CA type MAC / control and baseband signals for IEEE 802.11a connection. A MAC / BB chip that performs a function and outputs frequency information of the set service band and a TDD control signal; Filter switching to provide a frequency synthesis control signal to each RF chip according to the frequency information output from the MAC / BB chip to synthesize a corresponding frequency in each RF chip, and to set a bandwidth corresponding to the frequency information. Switching signal combination unit for generating a signal; And a filter switching unit for connecting any one of the 5 MHz band filter and the 20 MHz band filter between the corresponding RF chip and the MAC / BB chip according to the filter switching signal.

That is, the dual bandwidth wireless terminal device distinguishes a 2.3 GHz signal and a 2.4 GHz signal, and when the service is performed for the 2.3 GHz signal, the service bandwidth is 5 MHz, and when the service is performed for the 2.4 GHz signal, the service bandwidth is automatically set to 20 MHz. Adjust Distinguishing the 2.3GHz signal from the 2.4GHz signal and setting the use frequency may be performed according to the IEEE 802.11a channel number.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Referring to FIG. 1, according to the present invention, a system for providing a portable Internet service in a 2.3 GHz band and a wireless LAN service in a 2.4 GHz band includes a service interworking server 11, an IP network 12, a network configuration device 13, A 2.3 GHz band portable Internet base station 14, a 2.4 GHz band AP (Access Point) device 15, and the like. The server 11 for providing a service may provide a user's authentication and billing service including a billing server, an authentication server, a database, and the like. The network configuration device 13 may include an A / C and an L2 or L3 switch. In addition, the 2.4 GHz band WLAN AP device 15 is installed in the indoor or hotspot area, such as 17 to use the wireless Internet service.

However, the 2.3GHz band portable Internet service can provide services in a wider area than the 2.4GHz band WLAN service, such as an apartment complex, campus, and park (16), and complements the 2.4GHz band WLAN service in various regions. Can be provided enemy or mutually conflicting. Therefore, in some regions, both the portable Internet service and the wireless LAN service can be used, so that a user can select and use one of them, and in some regions, only one of the two services may be available.

Referring to FIG. 2, the dual-band wireless terminal device used to provide a portable Internet service of 2.3 GHz band and a wireless LAN service of 2.4 GHz band according to the present invention includes antennas 31 and 2.3 of 2.3-2.5 GHz band. RF input / output unit 32 in the 2.5 GHz band, 2 GHz band RF chip 33, switch unit 34, termination unit 35, 5 GHz band RF chip 36, MAC / BB chip 37, etc. do. In particular, by dividing the 2.3GHz signal and 2.4GHz signal, the service bandwidth is automatically adjusted to 5MHz when serving the 2.3GHz signal, and the service bandwidth is automatically adjusted to 20MHz when serving the 2.4GHz signal.

The antenna 31 of the 2.3 ~ 2.5GHz band can transmit and receive signals in the 2.3GHz band and 2.4GHz band. In this case, since both the 2.3GHz band portable Internet service and the 2.4GHz band WLAN service use the TDD (Time Division Duplex) method, the same antenna can be used.

The RF input / output unit 32 of the 2.3 to 2.5 GHz band may include a time RF switch, a wideband RF filter, a low noise amplifier, a power amplifier, and the like, and transmit and receive signals in the 2.3 GHz band and the 2.4 GHz band.

The 2 GHz band RF chip 33 sets the frequency of the 2.3 GHz band and the frequency of the 2.4 GHz band through the IEEE 802.11a channel number.

The switch unit 34 separates signals in the 5 GHz band, the 2.3 GHz band, and the 2.4 GHz band, respectively. In other words, the signal of 5GHz band which is not used is terminated and mobile Internet service of 2.3GHz band and wireless LAN service of 2.4GHz band are distinguished according to IEEE 802.11a channel number selection. At this time, the termination part 35 absorbs / removes signals of the divided 5 GHz band without reflected waves.

The 5 GHz band RF chip 36 sets the frequency of the 5 GHz band through the IEEE 802.11a channel number. At this time, the frequencies used by the respective RF chips 33 and 36 are synthesized by a frequency synthesizer, which is controlled by a frequency synthesis control signal supplied from the switching signal combination unit 39.

The MAC / BB chip 37 interfaces with various user terminals such as personal computers (PCs), notebooks, and personal digital assistants (PDAs) to receive service band information from the terminals, and CSMA / CA (Carrier Sense) for IEEE 802.11a connection. It performs multiple access / collision avoidance (MAC) and MAC control, and performs modulation and demodulation of the baseband signal.

In the manufacture of such a dual bandwidth wireless terminal device, the frequency is separately classified according to a service (for example, 2.3 GHz to 2.4 GHz for portable Internet service and 2.4 GHz to 2.5 GHz for wireless LAN service), thereby not configuring a separate RF means. However, it is desirable to use broadband components to accommodate the entire band of 2.3GHz to 2.5GHz with one RF means. These RF means uses a broadband filter that can remove only the spurious caused by its own harmonic components resulting from its own frequency mixing and components that can affect adjacent services (services using frequencies other than 2.3 GHz to 2.5 GHz). The filter switching unit 38 in front of the MAC / BB chip of the receiving circuit selectively removes interference due to adjacent channels by selectively using a 20 MHz band filter for a WLAN service and a 5 MHz band filter for a portable Internet service.

Referring to FIG. 3, the 2.3 GHz portable Internet service band and the 2.4 GHz wireless LAN service band may be set according to the IEEE 802.11a channel number using a CPU in a terminal such as a PC, a notebook, or a PDA in a Window OS environment. The terminal is interfaced with the MAC / BB chip 37, the frequency information signal set in the terminal is transmitted to the MAC / BB chip 37, the 5GHz RF chip 36 at the control terminal of the MAC / BB chip 37 The frequency synthesizer is transmitted to the switching signal combination unit 39 as a signal for controlling at the frequency.

The switching signal combination unit 39 distinguishes a 2.3 GHz portable Internet service signal from a 2.4 GHz public WLAN signal, generates a filter switching signal using a frequency information signal, and also includes a frequency synthesizer of the RF chips 33 and 36 ( frequency synthesizer to generate a frequency control signal to control the frequency to be generated.

The filter switching unit 38 operates according to the generated filter switching signal to select a 5 MHz band filter for 2.3 GHz portable Internet service and a 20 MHz band filter for 2.4 GHz WLAN service. In addition, the frequency control signal is provided to the 2 GHz RF chip 33 and the 5 GHz RF chip 36 to change the frequency synthesizer of the RF chip and finally to change the LO (Local Oscillator) frequency provided to the frequency mixer inside the RF chip. The frequency input and output to the RF chip is changed.

An example of a process of selecting a band pass filter and setting a frequency will be described in more detail with reference to FIG. 4.

When receiving a message for selecting a service user or setting an automatic frequency from the CPU in the terminal (S51), it is selected whether to use the 2.3GHz portable Internet service or the 2.4GHz public WLAN service (S52).

First, in the case of 2.3 GHz portable Internet service, the IEEE 802.11a channel numbers 94 to 112 are first set through the MAC / BB chip 37 (S53-1). Information related to this channel is input to the switching signal combination unit 39 to generate a frequency control signal for changing the filter switching signal and the frequency synthesizer in the RF chip 36 in the 5 GHz band (S53-2). The filter switching signal is input to the filter switching unit 38 to connect the 5 MHz band filter to the circuit (S53-3), and the frequency control signal changes the frequency synthesizer in the RF chip 36 of the 5 GHz band to the RF chip of the 5 GHz band. In the input / output terminal (36), the center frequency of 5.475 to 5.560 GHz is inputted and outputted (S53-4). These I / O frequencies are transmitted from the RF chip 33 of the 2 GHz band to the 3.168 GHz frequency synthesizer LO (Local Oscillator) together with the frequency mixer and in the 2.3 GHz band of the transmit / receive center frequency of 2.307 to 2.392 GHz (OFDM, CSMA / A frequency band for the mobile Internet service of CA may be generated (S53-5).

Secondly, in case of the 2.4 GHz WLAN service, first, IEEE 802.11a channel numbers 116 to 128 are set through the MAC / BB chip 37 (S54-1). Information related to this channel is input to the switching signal combination unit 39 to generate a frequency control signal for changing the filter switching signal and the frequency synthesizer in the RF chip 36 in the 5 GHz band (S54-2). The filter switching signal is input to the filter switching unit 38 to connect the 20 MHz band filter to the circuit (S54-3), and the frequency control signal changes the frequency synthesizer in the RF chip 36 of the 5 GHz band, thereby RF of the 5 GHz band. In the input / output terminal of the chip 36, a center frequency of 5.580 to 5.540 GHz is inputted and outputted (S54-4). The input / output frequency may be generated in the 2.4 GHz band of the transmit / receive center frequency of 2.412-2.472 GHz through the frequency mixer with the frequency synthesizer LO of 3.168 GHz in the RF chip 33 of the 2 GHz band. (S54-5).

In this case, the most important part is to use two filters with different bandwidths and use the appropriate filter for each service. In addition, the 2.4GHz band wireless LAN signal can optionally provide a physical specification of 802.11g based on the physical specification of 802.11b, the mobile Internet service signal of the 2.3GHz band is an OFDM signal like 802.11a, CSMA / Carrier Sense, Multiple Access / Collision Avoidance (CA)

Referring to FIG. 5, an example of a process in which a dual bandwidth wireless terminal device operates when a user powers up a terminal to use a service will be described.

When the power of the terminal equipped with the dual-bandwidth wireless terminal device according to the present invention is turned on (S61), the received signal is first confirmed by scanning the 2.3GHz band portable Internet frequency which is a wide area service (S62). If the received signal is confirmed, it is checked whether the received signal level is a good level that can be communicated (S62-1). If the received signal is a good level, the receive filter is set to a 5 MHz band filter (S622), and the reception state is good. S64). However, as a result of the check in step S62, if the received signal of the 2.3 GHz band portable Internet frequency is not confirmed or is not a good level in step S62-1, it indicates that the 2.3 GHz signal reception state is poor (S62-3).

On the other hand, when the signal of the 2.3GHz band portable Internet frequency is not received in step S62 or the reception state is poor, the 2.4GHz band frequency, which is a wireless LAN service, is scanned to check the received signal (S63). If the received signal is not confirmed as a result of the checking in step S63, it indicates that there is no frequency available (S65), and the flow returns to step S62 to resume scanning. When the received signal is confirmed in step S63, it is checked whether the signal level is a communicable level (S63-1). If the received signal level is a good level, the reception filter is set to a 20 MHz band filter (S63-2), and then the reception state is received. Indicates good (S64).

However, if the result of the check in step S63-1 is not a good level, it indicates that the 2.4GHz signal reception state is poor (S63-3), and returns to step S62 to start scanning again.

At this time, the selection of the service can be configured to use both the manual mode selected by the user and the automatic mode to be controlled in a preset state by the user. In addition, the dual-bandwidth wireless terminal device according to the present invention can be preferably implemented in the form of a card that can be easily mounted on a variety of user terminals. Of course, if a higher antenna gain is desired, the antenna 31 of the 2.3 GHz to 2.5 GHz band connected to the RF input / output unit 32 of the 2.3 GHz to 2.5 GHz band may be replaced with a high gain external antenna.

The present invention is not limited to the above-described embodiments and can be variously modified and implemented by those skilled in the art without departing from the technical spirit of the present invention.

According to the present invention, it is possible to provide both the portable Internet service of the 2.3GHz band and the wireless LAN service of the 2.4GHz band through an integrated dual bandwidth wireless terminal device. In addition, when the dual bandwidth wireless terminal device is manufactured, commercial chips of the conventional dual frequency wireless LAN cards of the 2.4 GHz band and the 5 GHz band, and core components are commonly used, can be manufactured at a lower cost.

Claims (1)

A 5 MHz band filter, which is a bandwidth for portable Internet services; A bandpass filter of 20MHz, which is a bandwidth for WLAN service; It interfaces with various terminals such as personal computer (PC), notebook, personal digital assistant (PDA), etc. to receive the set service band from the terminal, and modulates and demodulates the CSMA / CA type MAC / control and baseband signals for IEEE 802.11a connection. A MAC / BB chip that performs a function and outputs frequency information of the set service band and a TDD control signal; Filter switching to provide a frequency synthesis control signal to each RF chip according to the frequency information output from the MAC / BB chip to synthesize a corresponding frequency in each RF chip, and to set a bandwidth corresponding to the frequency information. Switching signal combination unit for generating a signal; And And a filter switching unit for connecting any one of the 5 MHz band filter and the 20 MHz band filter between a corresponding RF chip and a MAC / BB chip according to the filter switching signal.

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