JP2011517371A - Cellular carrier conversion method - Google Patents

Abstract

A plurality of carrier signals in the wideband signal are converted into a plurality of digital carrier signals (100). Each of the plurality of carrier signals is at a respective frequency in the broadband signal. At least one of the plurality of digital carrier signals is converted to a different frequency (300).

Description

PRIORITY CLAIM This US patent application is filed under US Patent Act (35 USC) Section 119, US Provisional Patent Application No. 61 / 007,907, first filed on June 28, 2007. Claim priority over issue. U.S. Provisional Patent Application No. 61 / 007,907 was modified from U.S. Patent Application No. 11 / 819,619, filed on June 18, 2007, on October 18, 2007. The entire contents are incorporated herein.

  In wireless network systems, such as code division multiple access (CDMA) networks, a certain amount of spectrum is available for the system. The amount or bandwidth of this spectrum may vary depending on standards, government regulations, etc. that regulate this wireless network system. The location of the allocated bandwidth within this spectrum may also vary depending on standards, government regulations, etc. that regulate this wireless network system. Further, the number of carriers supported by the allocated bandwidth may also depend on the amount of allocated bandwidth, the location of the bandwidth in the spectrum, standards, etc.

  For example, one 5 MHz CDMA system includes three (3) carriers, each occupying a bandwidth of 1.25 MHz out of a bandwidth of 5 MHz. A radio frequency signal in a carrier frequency band having a bandwidth of 1.25 MHz can accommodate up to 64 channels (voice or data).

  The allocation of carriers to frequency bands in the allocated bandwidth, the amount of allocated bandwidth, and the position of the allocated bandwidth are fixed within this scheme. That is, using the 5 MHz CDMA scheme described above as an example, two different 5 MHz CDMA schemes can have different carrier frequency band assignments and / or have 5 MHz bandwidths arranged differently. .

  Because some components of a wireless system (eg, receivers, etc.) depend on allocated bandwidth, allocated bandwidth location in the system, frequency band allocation, etc., these of the wireless system Components can often be system specific. That is, components of one system are often not usable in another system. This lack of flexibility results in higher design and fabrication costs for wireless system components.

  Exemplary embodiments of the present invention provide a cellular carrier conversion method.

  In one exemplary embodiment, a cellular carrier conversion method is the step of converting a plurality of carrier signals in a wideband signal into at least one individual digital carrier signal, wherein each of the at least one individual carrier signal is , At each frequency in the broadband signal, and converting at least one individual digital carrier signal to a different frequency.

  Exemplary embodiments of the present invention will become more fully understood from the detailed description and accompanying drawings set forth herein below, which are shown by way of illustration only and as such. The exemplary embodiments of the present invention are not limited.

It is the figure before the conversion which shows the state in which the carrier has occupied the full band of 10 MHz by one Embodiment as an example of this invention in a wide band. FIG. 2 is a block diagram illustrating a base station adapted to be used in one embodiment as an example of the present invention. 6 is a flowchart illustrating a carrier conversion method according to an exemplary embodiment of the present invention. FIG. 6 is a block diagram of a base station adapted to be used in another example embodiment of the present invention. 6 is a flowchart illustrating another carrier conversion method according to an embodiment of the present invention. FIG. 3 is a block diagram of a base station adapted to be used in another example embodiment of the invention. 6 is a flowchart illustrating another method for converting a carrier according to an exemplary embodiment of the present invention. FIG. 3 is a block diagram of a base station adapted to be used in another example embodiment of the invention. FIG. 6 shows the state of the carrier before and after conversion according to another exemplary embodiment of the present invention. FIG. 6 is a block diagram of a base station adapted to be used in another embodiment as an example of the present invention. FIG. 6 is a diagram illustrating carrier states before and after conversion, according to one embodiment of the present invention. 12 is a flow diagram illustrating a carrier conversion method illustrated in FIGS. 8-11 according to exemplary embodiments of the present invention.

  Although the exemplary embodiments of the present invention are described with reference to code division multiple access (CDMA) networks, those skilled in the art will recognize that the exemplary embodiments of the present invention may include other communication schemes such as WCDMA, It will be understood that the present invention can be applied to GSM, tones in WiMax (registered trademark, hereinafter the same), and the like.

  1 to 12 show cellular carrier (each carrier) conversion methods according to exemplary embodiments of the present invention. FIG. 1 shows a 10 MHz frequency band with four carriers before frequency conversion and after frequency conversion. Each carrier occupies a bandwidth of 1.25 MHz. Furthermore, each carrier may be for CDMA, WCDMA, GSM, or tone-in WiMax systems. Although the embodiments are also described with respect to operation at a base station, those skilled in the art will appreciate that embodiments of the method are not limited to base stations in practice.

  Referring to FIGS. 1, 2, and 3, in step 100, the base station 1 converts the entire bandwidth including four carriers into a digital signal by an analog-to-digital converter (ADC) 10 included in the base station receiver. Can be converted to The receiver may be a broadband wireless receiver. Although the figure shows four analog carriers, it is known to those skilled in the art that the carrier may be a single digital wideband signal. If the carrier is a single digital wideband signal, step 100 is skipped.

  At step 200, the digital carrier is further processed by digital filter 20. A digital representation of a 10 MHz bandwidth is converted into four digital representations (signals) consisting of four separate 1.25 MHz carriers.

  At step 300, the digital signal is then sent to a conversion engine 30, for example a frequency converter. The conversion engine converts one or more of the four digital signals to a new frequency. The frequency at which a particular carrier is present at the input of the receiver can be converted by the conversion engine 30 to a new frequency. Digital signal conversion is performed in the digital domain.

  In step 400, the converted digital signal is sent to a digital-to-analog converter (DAC) 40 for conversion to an analog signal. This analog signal can be sent to a radio frequency (RF) processor 50 to be further filtered and amplified in step 500, and then the analog baseband signal is transmitted to the end point 60. Optionally, after individual carriers are separated and converted, separate D / A stages can be used to generate four different analog signals. As another option, digital processing may be performed on the converted carrier to generate a wideband signal (the bandwidth may be equal to the bandwidth at the input, eg, 10 MHz). The wideband signal can then be sent to the DAC 40.

  As described above, in the exemplary embodiment of the present invention, by providing the frequency with flexibility, a smooth transition between communication frequencies is possible, and the amount of usage and the amount of usage increased. It is possible to deal with the capacity requirements arising from. Furthermore, signal radio output from a base station with multiple carriers can be used to drive the output at multiple locations with fewer carriers.

  Another cellular carrier conversion method according to an exemplary embodiment of the present invention is shown in FIGS. For the sake of simplicity, detailed descriptions of similar steps for the example embodiment shown in FIGS. 2 and 3 may be omitted.

  Referring to FIGS. 4 and 5, in steps 100 and 200, the carrier is converted by the ADC 10, and the converted digital signal is filtered by the digital filter 10. At step 250, each digital signal can be packetized by the packetizer 25 in a known manner to generate, for example, four data packet streams. At step 300, the digital packet stream is sent to the conversion engine 30 for conversion to a new frequency. This digital packet stream can be sent via, for example, an Ethernet network. The converted digital packet stream is further sent to the DAC 40 in step 400 for conversion to an analog signal. This analog signal can be sent to a radio frequency (RF) processor 50 at step 500 for further filtering and amplification, which is then transmitted to an end point.

  Another cellular carrier conversion method according to an exemplary embodiment of the present invention is shown in FIGS. For the sake of simplicity, detailed descriptions of similar steps for the example embodiment shown in FIGS. 2-5 may be omitted.

  Referring to FIGS. 6 and 7, in step 100 and step 200, the carrier is converted by the ADC 10, and the converted digital signal is filtered by the digital filter 20. At step 260, each digital signal can be packetized by packetizer 25, each of which can be further concatenated by concatenation unit 27 into a single concatenated digital packet stream. . The connection unit 27 can be implemented by hardware or software. At step 300, the concatenated digital packet stream is sent to the conversion engine 30 for conversion to a new frequency. The newly converted and concatenated digital packet stream is sent to the DAC 40 in step 400 for conversion to an analog signal. This analog signal can be sent to a radio frequency (RF) processor 50 for further filtering and amplification at step 500, which is then transmitted to end point 60.

  8, 9 and 12 illustrate another cellular carrier conversion method according to an exemplary embodiment of the present invention.

  Referring to FIGS. 8, 9, and 12, in steps 100 and 200, the carrier is converted by the ADC 10, and the converted digital signal is filtered by the digital filter 20. At step 250, each digital signal can be packetized by the packetizer 25. As shown in FIGS. 8, 9, and 12, each digital packet stream (or alternatively, each packet or group of packets) can be sent at 270 to a different and different location on the transmitter. A single wideband signal with one or several carriers can be supplied to multiple locations, but the number of carriers in each single wideband signal is the same or the receiver input Less than the number of carriers received in. As can be seen in the example embodiment shown in FIGS. 8 and 9, a single wideband signal with one carrier can be sent to location A and another single wideband signal with two carriers can be sent. Location B can be sent, and another broadband signal with one carrier can be sent to location C.

  At each different location of the transmitter, at step 300, the digital packet (s) can be converted to a new frequency, for example by the respective conversion engine 30. The newly converted digital packet (s) is sent to the respective DAC 40 for conversion to an analog signal (s). The analog signal (s) are processed by each RF processor 50 and transmitted to the end point 60 in steps 400 and 500, respectively.

  10, 11 and 12 illustrate another cellular carrier conversion method according to an exemplary embodiment of the present invention.

  Referring to FIGS. 10, 11, and 12, in step 100 and step 200, the carrier is converted by the DAC 10, and the converted digital signal is filtered by the digital filter 20. At step 250, each digital signal can be packetized by the packetizer 25. At step 270, each digital packet stream (or alternatively, each packet or group of packets) can be forwarded to a different, different location on the transmitter. As shown in FIGS. 10 and 11, a single wideband signal with only one carrier can be provided to one of the transmitter locations. At different and different locations of the transmitter, the conversion engine 30 converts each digital packet to a new frequency. The frequency of the four carriers differs at the receiver input, but each conversion engine 30A-30D at a different location in the transmitter converts the respective packet signal to the same frequency. Accordingly, in step 500, each packet signal is transmitted at the same frequency. Such example embodiments may be applied where only access to a single carrier bandwidth is available, but may have the advantage of being cost effective when using multi-carrier radio technology. desired.

  Although exemplary embodiments of the present invention have been described with respect to a cellular carrier that occupies a frequency band having four cellular carriers and a broadband signal with a bandwidth of 10 MHz, the number of cellular carriers and the number of broadband signals It will be appreciated that the bandwidth can be changed without departing from the scope of the present invention.

  Exemplary embodiments of the present invention provide frequency flexibility. Flexibility in frequency allows for a smooth transition to the government allocation of communication frequencies, and a smooth transition to address the increasing usage and capacity requirements that result from the increased usage Become. This flexibility in frequency can be achieved by software in the digital domain. Moreover, signal radio output from a base station with multiple carriers can be used to drive multiple output remote radio heads with fewer carriers.

  The exemplary embodiments of the present invention also allow wireless service providers to locate carriers to better manage interference and optimally handle cellular traffic.

  Having thus described exemplary embodiments of the present invention, it will become apparent that the present invention can be modified in many ways. For example, although one implementation of the present invention has been described with respect to a CDMA scheme, it will be appreciated that the present invention is applicable to other schemes including, for example, WCDMA, GSM, WiMax, and the like. Such variations are not to be regarded as a departure from the invention, and all such modifications are intended to be included within the scope of the invention.

Claims (10)

A carrier conversion method,
Converting (100) at least one analog carrier signal in the wideband signal to at least one digital carrier signal, wherein the at least one analog carrier signal is at a respective frequency in the wideband signal;
A method comprising converting (300) at least one digital carrier signal to a different frequency. Filtering (200) the at least one digital carrier signal;
The method of claim 1, wherein the converting step (300) converts the filtered at least one digital carrier signal.   The method of claim 1, further comprising digitally processing (50) the converted at least one carrier signal to generate a broadband signal.   The method of claim 1, further comprising converting (400) the at least one digital carrier signal back into at least one analog carrier signal.   5. The method of claim 4, wherein in a separate D / A stage, the at least one digital signal is converted (400) to the at least one analog carrier signal. Amplifying and filtering the converted at least one analog carrier signal (50);
Transmitting the amplified and filtered at least one signal to an end point (500).   The method of claim 1, wherein the at least one carrier is a carrier in a code division multiple access (CDMA) network.   The at least one carrier is one of a wideband code division multiple access (WCDMA) scheme, a global system for mobile communications (GSM) scheme, and a tone-in WiMax (Worldwide Interoperability Access) scheme. The method of claim 1, wherein   The method of claim 1, further comprising packetizing (250) each of the at least one digital carrier signal into at least one digital packet stream.   The method of claim 9, further comprising concatenating (260) the at least one digital packet stream.

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