KR100348705B1 - A Base station transceiver subsystem capable of multi-carrier transmission and receipt - Google Patents

Abstract

The present invention relates to a base station capable of transmitting and receiving a multicarrier to transmit and receive signals of a multicarrier while improving hardware complexity by improving a structure and expanding a shareable part. Phase locked loop means for holding; At least three uplink frequency converting means for applying a signal from said phase locked loop means to a signal of a predetermined transmission frequency band by applying it to a currently input modulation signal; And receiving means for receiving a signal input through a carrier after determining a receiving frequency according to a signal output from any one of the at least three uplink frequency converting means, uplink converting means, thereby implementing a multicarrier 3x mode. By allowing the three transmitters to share the phase-locked loop part and fitting the PLL lock of the receiver signal to the output signal from the second transmitter, the size of the transmitter of the base station is minimized as well as the size of the base station itself. do.

Description

A base station transceiver subsystem capable of multi-carrier transmission and receipt}

The present invention relates to a base station capable of multicarrier transmission and reception, and more particularly, to a base station capable of transmitting and receiving multicarriers in a next generation mobile communication network such as IMT-2000.

The third generation mobile telecommunications service, called International Mobile Telecommunications (IMT-2000), is a mobile telecommunications system that makes recommendations in the TG / 1 of ITU-R aiming at the service in the early 2000s.

This third generation mobile communication system is a mobile communication system that uses a wireless link to connect various communication services supported by a fixed communication network such as PSTN / ISDN / B-ISDN according to a mobile user's request.

The frequency bands used are 1,885 MHz to 2,025 MHz and 2,110 MHz to 2,200 MHz, as determined in WARC (now replaced by WRC) -92, which not only provide existing communication services but also provide a higher level of service through advanced technology. In the next generation mobile communication system, various types of mobile terminals that can be connected to a terrestrial or satellite network are used for mobile communication or fixed communication.

IMT-2000 is able to interoperate with various systems, has high service compatibility by worldwide operation, and has the features of using small size and light weight terminal with high quality.

IMT-2000 is a mobile communication system that provides not only voice and data but also multimedia services such as high-speed data and video communication up to 2Mbps. It introduces the concept of layer cell (pico, micro, macro cell, etc.) I aim to roam.

In addition, IMT-2000 uses a total of 230 MHz in the common frequency band (1,885 MHz to 2,025 MHz, 2,110 MHz to 2,200 MHz) worldwide, and the satellite portion of the IMT-2000 is limited to the bands 1,980 to 2,010 MHz and 2,170 to 2,200 MHz. As a result, international roaming is possible because it uses a common wireless standard.

In this way, IMT-2000 integrates the existing terrestrial mobile communication and satellite mobile communication systems so that the mobility of the terminal can be freely moved, the personal mobility that the subscriber can receive from any terminal, and the voice on the go. It aims to satisfy the service mobility and the like that can be used.

In other words, IMT-2000 is a third generation mobile communication system that integrates existing mobile communication systems to provide international roaming services, multimedia services, and personalized communication services.

However, the IMT-2000 service, which has been pursuing global roaming through the integration of technology around the world, is divided into Europe / Japan synchronous (W-CDMA) and North American synchronous (cdma2000 3x) in the final standardization stage. It is done.

In the asynchronous method, both the uplink and the downlink are configured as direct spread methods, but in the synchronous method, the downlink is configured in a 3x mode (multicarrier) by three times the existing 1x (= 1.25MHz) carrier. Synchronous uplink is configured by direct spread method. In this situation, the synchronous base station transmitter and the mobile station receiver must transmit and receive a 3x mode signal.

Accordingly, three identical transmitters are required for the base station transmitter to transmit three carriers. In this case, the complexity of the base station transmitter is increased, which is very disadvantageous in terms of economics, and the volume of the entire base station also increases.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and a base station capable of multicarrier transmission and reception capable of transmitting and receiving a signal of a multicarrier while improving the hardware complexity by improving the structure and expanding the shareable part is provided. The purpose is to provide.

1 is a block diagram of a base station capable of multi-carrier transmission and reception according to an embodiment of the present invention.

※ Explanation of code for main part of drawing

10: phase locked loop portion 12, 20, 28, 46: divider

14, 22, 30, 58: automatic gain controller 16, 24, 32, 50: band filter

18, 26, 34, 52: Mixer 36: Combiner

38 filter 40 driving amplifier

42: power amplifier 44: duplexer

48: low noise amplifier 54: intermediate frequency amplifier

56: intermediate frequency surface acoustic wave filter 60: RF detector

70: first uplink frequency converter 80: second uplink frequency converter

90: third uplink frequency converter 100: receiver

In order to achieve the above object, a base station capable of multicarrier transmission and reception according to a preferred embodiment of the present invention comprises: phase-locked loop means for maintaining an input reference signal source at a constant phase angle; At least three uplink frequency converting means for applying a signal from said phase locked loop means to a signal of a predetermined transmission frequency band by applying it to a currently input modulation signal; And receiving means for receiving a signal input through a carrier after determining a reception frequency according to a signal output from any one of the at least three uplink frequency converting means.

Hereinafter, a base station capable of multicarrier transmission and reception according to an embodiment of the present invention will be described with reference to the accompanying drawings.

1 is a block diagram of a base station capable of multi-carrier transmission and reception according to an embodiment of the present invention.

A base station according to an embodiment of the present invention includes a phase locked loop unit 10 for maintaining a constant phase angle with respect to an input reference signal source (reference frequency); After the data to be transmitted is I / Q modulated and inputted to the input signal (IF signal), the signal from the phase locked loop unit 10 is up-converted and then the signal (RF signal) of the corresponding channel FA # 1 is applied. A first uplink frequency converter 70 for outputting a); A signal (RF signal) of a corresponding channel (FA # 2) is subjected to up-frequency conversion by applying a signal from the phase-locked loop unit 10 to a signal (IF signal) inputted with I / Q modulation. A second uplink frequency converter 80 for outputting the; A signal (RF signal) of a corresponding channel (FA # 3) is up-converted by applying a signal from the phase-locked loop unit 10 to an input signal (IF signal) in which data to be transmitted is I / Q modulated. A third uplink frequency converter 90 for outputting a; A receiver 100 for determining a transmission frequency according to a signal (RF signal) output from the second uplink frequency converter 80 and receiving a signal input through a carrier; A combiner 36 that sums signals of channels FA # 1, FA # 2, and FA # 3 output from the first to third uplink frequency converters 80; A filter (38) for removing unnecessary noise from the signal output from the combiner (36); A driving amplifier 40 for transmitting a signal passing through the filter 38; A power amplifier 42 for amplifying the signal output from the driving amplifier 40; And a multicarrier transmitted from a mobile terminal (not shown) (signals of three channels FA # 1, FA # 2, FA # 3 in the embodiment of the present invention are bundled into one carrier (5 MHz in bandwidth), Such carriers are continuous) and a duplexer 44 for transmitting carriers to the mobile terminal (not shown).

Here, the filter 38 may be a band pass filter, a dielectric filter or a surface acoustic wave (SAW) filter.

The first uplink frequency converter 70 divides the signal from the phase locked loop unit 10 at a predetermined frequency division rate 12; An automatic gain controller 14 which performs gain control to accommodate the operation signal range of the antenna transmitting end with respect to the modulated signal input from the I / Q modulator, and makes a constant signal level; A band pass filter (16) for passing only signals of a specific bandwidth to remove unnecessary noise among the signals output from the automatic gain controller (14); And a mixer 18 for mixing the signal passing through the band filter 16 and the output signal of the divider 12 to up-convert the frequency.

The second uplink frequency converter 80 divides the signal from the phase-locked loop unit 10 at a predetermined frequency divider 20; An automatic gain controller 22 which performs gain control to accommodate the operating signal range of the antenna transmitting end with respect to the modulated signal input from the I / Q modulator and makes the signal level constant; A band pass filter 24 for passing only a signal having a specific bandwidth to remove unnecessary noise from the signal output from the automatic gain controller 22; And a mixer 26 for mixing the signal passing through the band filter 24 and the output signal of the divider 20 to up-convert the frequency.

The third uplink frequency converter 90 divides the signal from the phase locked loop unit 10 at a predetermined frequency division ratio 28; An automatic gain controller 30 which performs gain control to accommodate the operating signal range of the antenna transmitting end with respect to the modulated signal input from the I / Q modulator, and makes a constant signal level; A band pass filter (32) for passing only signals having a specific bandwidth to remove unnecessary noise among the signals output from the automatic gain controller (30); And a mixer 34 for mixing the signal passing through the band filter 32 and the output signal of the divider 28 to up-convert the frequency.

Here, the frequency division ratios of the frequency divider 12, the frequency divider 20, and the frequency divider 28 are mutually different.

The receiver 100 includes: a divider 46 for dividing the signal from the phase locked loop unit 10 at a predetermined frequency division rate; A low noise amplifier 48 for lowering noise included in the signal of each channel received through the duplexer 44 and amplifying the original received channel signal; A band pass filter (50) for removing unnecessary noise from a channel signal in a high frequency carrier through the low noise amplifier (48); The band mixer (52) mixing an output signal of the signal and the frequency divider 46 through the filter 50 for frequency down-converted (i.e., converted to an RF signal → IF signal); An intermediate frequency amplifier (54) for amplifying the intermediate frequency (IF) output from the mixer (52); An IF SAW filter 56 which passes only signals in a band of 1.25 MHz at an intermediate frequency output from the intermediate frequency amplifier 54; And an automatic gain controller 58 for performing a gain control to accommodate the dynamic range of the antenna receiver for the signal output from the intermediate frequency surface acoustic wave filter 56 and outputting a constant signal level to the I / Q demodulator 58. ).

The receiver 100 is configured to provide a duplex interval (eg, 190 MHz) to the channel FA # 2 signal output from the second uplink frequency converter 80 among the three uplink frequency converters 70, 80, and 90. The added value is determined as the reception frequency. Usually, the transmission frequency of the base station that performs wireless transmission / reception with the mobile terminal is 2110 MHz to 2170 MHz, and the reception frequency of the base station is 1920 MHz to 1980 MHz, so that the difference between the transmission frequency of the base station and the reception frequency (190 MHz) is the duplex. It becomes the interval.

In FIG. 1, reference numeral 60 denotes an RF detector for detecting a high frequency signal output from the power amplifier 42, and the RF detector 60 detects power at an output terminal of the power amplifier 42 to detect a detection signal. By sending the RF_DCT to a controller (not shown), the base station system determines whether there is an abnormality in the output terminal.

Next, an operation of a base station capable of multicarrier transmission and reception according to an embodiment of the present invention will be described.

The base station according to the embodiment of the present invention is applied to the synchronization method of the IMT-2000.

In the IMT-2000 synchronization method to which the present invention is applied, it is assumed that the forward link supports 3x mode (1.25MHz x 3). In order to support the 3x mode, the transmitter of the base station consists of three channel signals each having a bandwidth of 1.25 MHz.

For example, in order to transmit 384 Kbps of data, 128 Kbps of data is loaded in one bandwidth, three signals are generated at baseband, and then the digital signals are converted into analog signals and the data to be transmitted is transmitted from the I / Q modulator. After the modulation is sent to each of the uplink frequency converter (70, 80, 90).

Accordingly, the respective uplink frequency converters 70, 80, and 90 convert the input signal (IF signal) into an RF frequency and output the RF frequency.

That is, the gain-adjusted signals of the automatic gain controllers 14, 22, and 30 of the respective uplink frequency converters 70, 80, and 90 remove noise components through the corresponding band filters 16, 254, and 32. It is input to one input of each mixer 18, 26, 34, and the other input of each mixer 18, 26, 34 is a phase locked loop section 10 and each of the dividers 12, 20, The divided signal is input through 28).

Accordingly, the respective mixers 18, 26, and 34 mix the two input signals and perform frequency up-conversion (i.e., conversion of IF signals to RF signals). The signals of channels FA # 1, FA # 2, FA # 3 output from the mixers 18, 26, and 34 (that is, signals having a bandwidth of 1.25 MHz) are summed in the combiner 36. Become.

The signal (signal having a bandwidth of 5 MHz) output from the combiner 36 includes an undesired wave due to intermodulation or the like, which may occur during the mixing process.

Thus, the signal output from the combiner 36 is passed through the filter 38, the unwanted wave is removed, and is transmitted to the duplexer 44 through the driving amplifier 40 and the power amplifier 42 to the antenna ( (Not shown).

In order to monitor the power of the base station to be transmitted, the RF detector 60 senses the power at the output terminal of the power amplifier 42 and sends a signal to the controller (not shown) through the RF_DCT signal. It is determined whether there is an abnormality in the output stage.

In addition, in the case of the reverse link (mobile terminal → base station), since the mobile terminal transmission is already made of three channel signals bundled together, one carrier having a bandwidth of 5 MHz is used.

Therefore, in the case of the receiving unit 100 of the base station receiving the same, as described above, the second frequency (that is, the signal of the channel FA # 2) is determined by adding the duplex interval to the second frequency among the three base station transmission frequencies. In addition, the use of a voltage controlled oscillator can be minimized by sharing a transmission / reception voltage controlled oscillator (VCO).

As described in detail above, according to the present invention, by implementing the multicarrier 3x mode, by allowing the three transmitters to share the phase-locked loop part and fitting the PLL lock of the receiver signal to the output signal at the second transmitter, In addition to minimizing the size of the transmitter of the base station, it is possible to minimize the size of the base station itself.

Further, by efficiently determining the multicarrier transmission frequency of the base station, the complexity of the base station hardware is improved.

On the other hand, the present invention is not limited only to the above-described embodiment, but can be modified and modified within the scope not departing from the gist of the present invention, the technical idea to which such modifications and variations are also applied to the claims Must see

Claims (4)

Phase locked loop means for maintaining an input reference signal source at a constant phase angle; At least three uplink frequency converting means for applying a signal from said phase locked loop means to a signal of a predetermined transmission frequency band by applying it to a currently input modulation signal; And And receiving means for receiving a signal input through a carrier after determining a receiving frequency according to a signal output from any one of the at least three uplink frequency converting means. Base station. The method of claim 1, The base station capable of multi-carrier transmission and reception, characterized in that when there are three uplink frequency converting means, the receiving means determines the signal output from the second uplink frequency converting means plus a duplex interval as a transmission frequency. The method of claim 1, Each of the uplink frequency converting means, A divider for dividing the signal from the phase locked loop means at a constant divider ratio; And And a mixer for mixing the currently input modulation signal with the output signal of the divider to up-convert the frequency. The method of claim 1, The receiving means, A divider for dividing the signal from the phase locked loop means at a constant divider ratio; A mixer for mixing the signal received through the duplexer and the signal from the divider to down-convert the frequency; And And a filter for extracting only signals of a specific band with respect to the signal output from the mixer.