CN101803178B - Method of translating cellular carriers - Google Patents

Abstract

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

Description

Method of changing cellular carrier

priority statement

This non-provisional US patent application claims priority under U.S.C. § 119 to US Provisional Patent Application No. 61/007,907, originally filed June 28, 2007. U.S. Provisional Patent Application No. 61/007,907, which was converted on October 18, 2007, from U.S. Patent Application No. 11/819,619, filed June 28, 2007, both applications are incorporated in their entirety here.

Background technique

In a wireless network system, such as a Code Division Multiple Access (CDMA) network, a certain amount of spectrum is available to the system. The amount of bandwidth of the spectrum may vary according to standards governing wireless network systems, government regulations, and the like. The location of the allocated bandwidth in the spectrum may also vary according to the standards governing the wireless network system, government regulations, and the like. Furthermore, the number of carriers supported by the allocated bandwidth may depend on the amount of allocated bandwidth, the location of the bandwidth within the spectrum, the standard, and the like.

For example, a 5MHz CDMA system includes three (3) carriers, each of which occupies 1.25MHz of the 5MHz bandwidth. A radio frequency signal of a carrier frequency band with a bandwidth of 1.25 MHz can hold up to 64 channels (voice or data).

Within the system, allocation of carriers to frequency bands in the allocated bandwidth, the amount of the allocated bandwidth, and the position of the allocated bandwidth are fixed. That is, taking the above-mentioned 5MHz CDMA system as an example, two different 5MHz CDMA systems may have different carrier frequency band allocations, and/or may have 5MHz bandwidths at different locations.

Several components of a wireless system (eg, receivers, etc.) may typically be system specific since they depend on the allocated bandwidth, location of the allocated bandwidth within the system, frequency band allocation, etc. That is, components of one system are generally not available in another system. This lack of flexibility leads to higher costs in the design and manufacture of wireless system components.

Contents of the invention

Example embodiments of the present invention provide a method of changing cellular carriers.

In an example embodiment, a method of converting a cellular carrier includes converting a plurality of carrier signals in a wideband signal into at least one separate digital carrier signal, each of the at least one separate carrier signals in a wideband signal at respective frequencies; and translating said at least one single digital carrier signal to a different frequency.

Description of drawings

Exemplary embodiments of the present invention will be more fully understood from the detailed description given below together with the accompanying drawings, which are given by way of illustration only and therefore are not limiting of the exemplary embodiments of the present invention.

Fig. 1 shows the situation before and after conversion of carriers in a wide frequency band occupying a total frequency band of 10 MHz according to an exemplary embodiment of the present invention;

Figure 2 shows a block diagram of a base station suitable for use in an exemplary embodiment of the invention;

FIG. 3 shows a flow chart of a method for changing a carrier according to an exemplary embodiment of the present invention;

Figure 4 is a block diagram of a base station suitable for use in another example embodiment of the invention;

FIG. 5 shows a flow chart of another method for changing carriers according to an exemplary embodiment of the present invention;

Figure 6 is a block diagram of a base station suitable for use in another example embodiment of the invention;

FIG. 7 shows a flow chart of another method for changing carriers according to an exemplary embodiment of the present invention;

Figure 8 is a block diagram of a base station suitable for use in another example embodiment of the invention;

FIG. 9 shows carriers before and after conversion according to another exemplary embodiment of the present invention;

Figure 10 is a block diagram of a base station suitable for use in another example embodiment of the invention;

FIG. 11 shows carriers before and after conversion according to an exemplary embodiment of the present invention; and

Fig. 12 shows a flow chart of the method for changing the carrier shown in Figs. 8-11 according to an exemplary embodiment of the present invention.

Detailed ways

Although example embodiments of the present invention will be described with reference to Code Division Multiple Access (CDMA) networks, those skilled in the art will recognize that example embodiments of the present invention may be applied to other telecommunications systems (e.g., WCDMA, GMS, WiMax, etc.) tone (tone), etc.).

1-12 illustrate a method of changing a cellular carrier (carrier) according to an example embodiment of the present invention. Figure 1 shows a 10 MHz frequency band with four (4) carriers before and after frequency conversion. Each carrier occupies 1.25MHz bandwidth. Again, the carrier can be used for tones in CDMA, WCDMA, GSM or WiMax systems. Furthermore, embodiments will be described with reference to operation at a base station, but those skilled in the art will recognize that, in implementations, method embodiments are not limited to a base station.

1, 2 and 3, at a base station 1, at step 100, an analog-to-digital converter (ADC) 10 included in a receiver of the base station may convert the entire bandwidth including four (4) carriers into a digital signal. The receiver may be a wideband radio receiver. Although four (4) analog carriers are shown in the figure, it is well known to those skilled in the art that the carrier could be a single digital wideband signal. If the carrier is a single digital wideband signal, step 100 is skipped.

In step 200, digital filter 20 further processes the digital carrier. Converts the digital representation of the 10MHz bandwidth into four (4) digital representations (signals) of four separate 1.25MHz carriers.

Then at step 300, the digital signal is sent to a translation engine 30 (eg, a frequency translator). The transform engine transforms one or more of the four (4) digital signals to a new frequency. The translation engine 30 may translate the frequency at which a particular carrier resides at the input of the receiver to a new frequency. Transformation of digital signals is done in the digital domain.

At step 400, the converted digital signal is sent to a digital-to-analog converter (DAC) 40 for conversion into an analog signal. The analog signal may be sent to a radio frequency (RF) processor 50 for further filtering and amplification, and then, at step 500 , the analog baseband signal is transmitted to endpoint 60 . Alternatively, separate D/A stages may be used to create four (4) different analog signals after the individual carriers are separated and transformed. Alternatively, the transformed carrier can be digitally processed to create a wideband signal (bandwidth can be equal to that at the input, eg 10MHz). The broadband signal can then be sent to the DAC 40.

As disclosed above in the exemplary embodiments of the present invention, frequency flexibility will allow smooth transitions between communication frequencies and handle increasing usage and the capacity requirements that may result from the increased usage. Furthermore, signal radio outputs from base stations with multiple frequencies can be used to drive outputs at multiple locations with fewer carriers.

4 and 5 illustrate another method of changing cellular carriers according to an example embodiment of the present invention. A detailed description of similar steps with reference to the example embodiments shown in FIGS. 2 and 3 may be omitted for brevity.

4 and 5, in steps 100 and 200 respectively, the ADC 10 converts the carrier wave, and the digital filter 10 filters the converted digital signal. At step 250, packetizer 25 may packetize each digital signal in a known manner to create, for example, four (4) streams of data packets. At step 300, a stream of digital packets is sent to the conversion engine 30 for conversion to the new frequency. The stream of digital packets may be sent over, for example, Ethernet. The transformed digital packet stream is also sent to the DAC 40 for conversion to an analog signal at step 400. The analog signal may be sent to a radio frequency (RF) processor 50 for further filtering and amplification, and then, at step 500, transmitted to the endpoint.

6 and 7 illustrate another method of changing cellular carriers according to an example embodiment of the present invention. Detailed descriptions of similar steps with reference to the example embodiments shown in FIGS. 2-5 may be omitted for brevity.

6 and 7, in steps 100 and 200 respectively, the ADC 10 converts the carrier, and the digital filter 20 filters the converted digital signal. At step 260, packetizer 25 may packetize each digital signal, and concatenation unit 27 may further concatenate each packet into a single concatenated digital packet stream. The cascading unit 27 can be realized by hardware or software. At step 300, a stream of concatenated digital packets is sent to the conversion engine 30 for conversion into the new frequency. The newly converted concatenated digital packet stream is sent to the DAC 40 for conversion to an analog signal at step 400. The analog signal may be sent to a radio frequency (RF) processor 50 for further filtering and amplification, and then, at step 500 , the concatenated analog signal is transmitted to endpoint 60 .

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

8, 9 and 12, in steps 100 and 200 respectively, the ADC 10 converts the carrier, and the digital filter 20 filters the converted digital signal. At step 250, packetizer 25 may packetize each digital signal. As shown in Figures 8, 9 and 12, at step 270, each stream of digital packets (or alternatively, each packet or group of packets) may be sent to a separate and distinct transmitter location. A single wideband signal having one or more carriers may be fed to multiple locations, but wherein the number of carriers in each single wideband signal is equal to or less than the number of carriers received at the input of the receiver. It can be seen that in the example embodiments shown in FIGS. 8 and 9, a single broadband signal with one carrier can be sent to location A; another single broadband signal with two carriers can be sent to location B; and a single broadband signal with two carriers can be sent to location B; Another single broadband signal of one carrier is sent to position C.

At each of the different transmitter locations, at step 300, for example, a corresponding transformation engine 30 may transform the digital packets into the new frequency. The newly converted digital packets are sent to the corresponding DAC 40 for conversion to analog. In steps 400 and 500 respectively, the corresponding RF processor 50 processes the analog signal, which is transmitted to the endpoint 60 .

Figures 10, 11 and 12 illustrate another method of changing cellular carriers according to an example embodiment of the present invention.

10, 11 and 12, in steps 100 and 200 respectively, the DAC 10 converts the carrier wave, and the digital filter 20 filters the converted digital signal. At step 250, packetizer 25 may packetize each digital signal. At step 270, each stream of digital packets (or alternatively, each packet or group of packets) may be transmitted to a separate and distinct transmitter location. As shown in Figures 10 and 11, a single broadband signal with only one carrier can be fed into one of multiple transmitter locations. At each of the separate and distinct transmitter locations, a translation engine 30 translates each digital packet into a new frequency. Although the four (4) carriers are of different frequencies at the input of the receiver, each conversion engine 30A-30D at a separate and different transmitter location converts each packet signal into the same frequency. Thus, at step 500, each packet signal is transmitted at the same frequency. This example embodiment is applicable where only the bandwidth of a single carrier is accessible, but the advantage of cost-effective use of multi-carrier wireless technology is desired.

Although the exemplary embodiment of the present invention has been described using a frequency band of four (4) cellular carriers and a cellular carrier occupying a 10 MHz bandwidth wideband signal, it will be appreciated that the number of cellular carriers and the bandwidth of the wideband signal may vary without departing from the present invention range subject to change.

Example embodiments of the present invention provide frequency flexibility. Frequency flexibility will allow a smooth transition to managed allocation of communication frequencies and handle increasing usage and resulting capacity requirements. The provision of this frequency flexibility is achievable in the digital domain by software. Furthermore, the signal radio output from a base station with multiple carriers can be used to drive multiple output remote radio heads with fewer carriers.

Example embodiments of the present invention will also enable wireless service providers to locate their carriers to better manage interference and optimally handle cellular traffic.

Having thus described example embodiments of the invention, it will be obvious that they may be varied in various ways. For example, although example implementations of the invention are described with reference to a CDMA system, it will be appreciated that the invention is applicable to other systems 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 fall within the scope of the invention.

Claims (9)

1. the method for a conversion carrier wave comprises:

A plurality of analog carrier signal in the broadband signal are converted to a plurality of digital carrier signals (100), and each in described a plurality of analog carrier signal is in the corresponding frequencies place in the broadband signal;

Described a plurality of digital carrier signal groupings are turned to a plurality of digital packet streams (250);

Send described digital packet stream (270) to different transmitter sites; And

With at least one the resident frequency translation in described a plurality of digital carrier signals to different frequency (300).

2. method according to claim 1 also comprises:

In described a plurality of digital carrier signals at least one carried out filtering (200);

Wherein, shift step (300) is carried out conversion at least one filtered digital carrier signal.

3. method according to claim 1 also comprises:

Carrier signal after at least one conversion is carried out digital processing (50), to create broadband signal.

4. method according to claim 1 also comprises:

Described at least one digital carrier signal is converted back at least one analog carrier signal (400).

5. method according to claim 4, wherein, described at least one digital signal is converted into described at least one analog carrier signal (400) in the D/A level of separating.

6. method according to claim 4 also comprises:

Analog carrier signal after at least one conversion is amplified and filtering (50); And

At least one amplification and filtered signal are sent to end points (500).

7. method according to claim 1, wherein, described at least one carrier wave is the carrier wave in the Code Division Multiple Access (CDMA) network.

8. method according to claim 1, wherein, described at least one carrier wave is one of following carrier wave: the tone in Wideband Code Division Multiple Access (WCDMA) WCDMA, global system for mobile communications GSM and the worldwide interoperability for microwave access WiMax system.

9. method according to claim 1 also comprises:

In described a plurality of digital packet streams each is carried out cascade (260).

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