Abstract:
A method, system, and medium are provided for testing a network communications component. A model of a substantially ideal communications network is provided and a test signal is generated at an input of the network model. An output signal from the model is transmitted to the network component. The signal is suitable for analyzing acoustic parameters of the network component. The acoustic parameters are analyzed based upon a response of the network component to the output signal.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   Not applicable. 
   STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
   Not applicable. 
   BACKGROUND 
   With the advancement of wireless technology, customer expectations of voice quality are increasing. Several types of fixed wireless or mobile wireless handset units are available in today&#39;s market. Moreover, various wireless carriers provide levels of voice quality that vary from carrier to carrier. 
   Research in the consumer and domestic markets suggests that the voice quality provided by, for example, U.S. wireless carriers, vary significantly from end-point customer premises equipment (CPE) unit to unit and also from brand to brand. The voice quality of wireless carriers have yet to reach the average voice quality of traditional fixed-line telephone networks. Furthermore, the increasing uses of wireless HUBs eliminate the need for a customer to have both a wireless account and a traditional land-line account. Wireless HUBs allow the customer to access a wireless network using, for example, a personal computer or traditional land-line phone. By measuring, fixing, and controlling the quality of the end-point wireless CPE (e.g., wireless HUB or wireless handset), it is possible to approach the voice quality of traditional fixed-line networks. 
   Referring to  FIG. 3A , there is illustrated block diagram of a system  300 A that illustrates a historical shortcoming associated with attempting to measure the acoustic quality of an endpoint: that the acoustic quality of the entire wireless network, including the end-point CPE, would be measured In system  300 A, a test signal is transmitted from an output  312 A of a digital speech language analyzer (DLSA)  302 A. The test signal propagates through a wall jack  316 A to a communications network. The network comprises a central office (CO)  318 A, and a cellular base station and antenna  320 A. The test signal is transmitted from antenna  320 A to a HUB  322 A. An input  314 A of DSLA  302 A receives the test signal. The test signal is then analyzed to determine voice quality. However, the overall voice quality includes distortion from network elements  318 A,  320 A, and HUB  322 A. 
   SUMMARY 
   Embodiments of the present invention provide a system and method for determining the acoustic quality of the wireless CPE by measuring the acoustic frequency responses. Further, embodiments of the present invention have several practical applications in the technical arts including the identification and evaluation of problems responsible for degrading voice quality in networks by the CPE coupled at end-points of the network. 
   In one embodiment, a method is provided for testing a network communications component. The method comprises of providing a model of a substantially ideal communications network, generating a test signal at an input of the network model, and providing an output signal from the model to the network component suitable for analyzing acoustic parameters of the network component. Finally, analyzing the acoustic parameters based upon a response of the network component to the output signal. 
   In another embodiment, a method is provided for evaluating acoustic qualities of a component in a network. The method comprises providing a network device that represents a substantially distortionless communications network, coupling the network device to the component, and introducing a test signal at an input of the network device. The method further includes providing an acoustic signal from the network device to the component in response to the test signal, and receiving at a measurement device an indication of the acoustic quality of the component, where the indication produced by the component is in response to the acoustic signal. Finally, based upon the indication, presenting data representing the acoustic quality of the component. 
   In yet another embodiment, a measurement system is provided for determining the acoustic quality of a communications component. The system comprises of a model with a substantially ideal communications network and a test-signal generator coupled to the network model for providing a test signal to the network model. The network model produces an acoustic signal in response to the test signal. Also, the system comprises a network component coupled to the network model. The network component produces an indication of acoustic quality in response to the acoustic signal. A data collection device is provided and coupled to the network component to receive the indication of acoustic quality and present data representing the acoustic quality of the network component. 

   
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
     Embodiments of the present invention are described in detail below with reference to the attached drawing figures, which are incorporated by reference herein and wherein: 
       FIG. 1  illustrates an exemplary network architecture  100  incorporating both land-line and wireless networks suitable for practice in accordance with an embodiment of the present invention; 
       FIGS. 2A and 2B  illustrate exemplary embodiments of a system for coupling end-point CPEs to a wireless HUB; 
       FIG. 3A  is a block diagram of a historical system for measuring acoustic quality; 
       FIG. 3B  illustrates an embodiment of the present invention illustrating a system  300  for measuring the acoustic quality of an end-point CPE; 
       FIGS. 4A-5B  illustrate, in graphical form, transmit, receive, and sidetone frequency responses for an the exemplary system of  FIG. 3B ; and 
       FIG. 6  illustrates an embodiment of a method for measuring the acoustic quality of an end-point CPE. 
   

   DETAILED DESCRIPTION 
   Embodiments of the present invention provide a system and method for analyzing the voice (acoustic) quality of end-point CPEs in a communications network. End-point CPEs include cell phones, analog phones, or wireless HUBs. A wireless HUB provides access to a wireless network by, for example, an analog phone or personal computer. This access to a customer&#39;s wireless carrier&#39;s network eliminates the need of a land-line connection provided by a traditional carrier. 
   Throughout this description, various technical terms are used. A definition of such terms can be found in  Newton&#39;s Telecom Dictionary  by H. Newton, 20th Edition (2004). These definitions are intended to provide a clearer understanding of the ideas disclosed herein but are in no way intended to limit the scope of the embodiments of the present invention. The definitions and terms should be interpreted broadly and liberally to the extent allowed by the meaning of the words offered in the above-cited reference. For example, whereas some distinguish the World Wide Web (WWW) as a subcomponent of the Internet, “web”—as used herein—should not be construed as limited to the WWW. Rather, “web” is intended to refer generally to the Internet and/or its related subnetworks and subcomponents. 
   As one skilled in the art will appreciate, the present invention may be embodied as, among other things: a method, system, or computer-program product. Accordingly, embodiments of the present invention may take the form of a hardware embodiment, a software embodiment, or an embodiment combining software and hardware. In one embodiment, the present invention takes the form of a computer-program product that includes computer-useable instructions embodied on one or more computer-readable media. 
   Computer-readable media include both volatile and nonvolatile media, removable and nonremovable media, and contemplates media readable by a database, a switch, and various other network devices. Network switches, routers, and related components are conventional in nature, as are means of communicating with the same. By way of example, and not limitation, computer-readable media comprise computer-storage media and communications media. 
   Computer-storage media, or machine-readable media, include media implemented in any method or technology for storing information. Examples of stored information include computer-useable instructions, data structures, program modules, and other data representations. Computer-storage media include, but are not limited to RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile discs (DVD), holographic media or other optical disc storage, magnetic cassettes, magnetic tape, magnetic disk storage, and other magnetic storage devices. These memory components can store data momentarily, temporarily, or permanently. 
   Communications media typically store computer-useable instructions—including data structures and program modules—in a modulated data signal. The term “modulated data signal” refers to a propagated signal that has one or more of its characteristics set or changed to encode information in the signal. An exemplary modulated data signal includes a carrier wave or other transport mechanism. Communications media include any information-delivery media. By way of example but not limitation, communications media include wired media, such as a wired network or direct-wired connection, and wireless media such as acoustic, infrared, radio, microwave, spread-spectrum, and other wireless media technologies. Combinations of the above are included within the scope of computer-readable media. 
     FIG. 1  illustrates an exemplary network architecture  100  incorporating both land-line and wireless networks. A call may originate from a cell phone  112  to an analog phone  114 B through a HUB  114 A. In one embodiment, a call originating from cell phone  112  to an analog phone coupled to a wireless HUB  114 B may propagate through a cellular tower  110 B, a base station  110 A, a first point of presence  120 , a land-line network  102 , a second point of presence  122 , base station  110 A, cellular tower  110 B, and HUB 114 A. In another embodiment, a call originating from cell phone  112  to an analog phone  116 B may traverse a path through cellular tower  110 B and base station  110 A, land-line network  102 , and then through a local exchange central office  118 . In each of the aforementioned exemplary embodiments, the variety of network elements each contribute to the distortion of or decrease in the voice quality of the call. Distortion may be introduced by any element comprising land-line network  102  or any element of a wireless network such as base stations  110 A, cellular towers  110 B or HUBs  114 A. Further increasing distortion is a home lookup registry (HLR)  124 C that is generally consulted through a cellular switch  124 A in order to establish the identity of a caller using cell phone  112 . 
   Each network element comprising network  100  should be optimized for maximum voice quality at an end-point CPE. Certain acoustic parameters should be measured or analyzed to determine optimum voice quality. These parameters include, but are not limited to, received acoustic quality of an end-point CPE, transmitted acoustic quality of an end-point CPE, sidetone sound levels, and linearity. Sidetones are the feature of a telephone handset that allows a user to hear themselves speak, acting as feedback that the phone is working. Sidetones are short-line echoes bled back into the earpiece, and too much sidetone creates an echo and noise to the far end. Linearity allows the user to hear the pitch and tone of the person to whom they are speaking. However, evaluation of the acoustic qualities of end-point CPEs separately, such as cellular phone  112  and home HUB  114 A, is particularly troublesome. Because of this it is difficult to identify whether the CPE or the network is responsible for the degradation of the voice quality. This is due in part to distortion propagated to the end-point CPE by elements comprising network  100 . 
   Referring now to  FIGS. 2A and 2B  in combination, there are illustrated several exemplary embodiments of a system  200  for coupling end-point CPEs to a wireless HUB  214  (which is also an end-point CPE). In  FIG. 2A , a land-line analog phone  210  may be coupled through a port  216  to wireless HUB  214 . Wireless HUB  214  communicates to, for example, cellular tower  110 B in  FIG. 1  through an antenna  218 . In  FIG. 2B , there is illustrated yet another embodiment of system  200  incorporating HUB  214 . In  FIG. 2B , system  200  comprises a back-plane  212  which couples land-line analog phones  210  and a personal computer  226  to wireless HUB  214  through ports  220 ,  222 , and  224 . Wireless HUB  214  communicates to network  100  through antenna  218 . In the embodiment illustrated in  FIG. 2B , analog phones  210  and personal computer  226  may be located on separate floors of a home. For example, one analog phone  210  may be coupled directly to HUB  214  on a first floor of the house, while another analog phone  210  located on a second floor of the house may be coupled to HUB  214  through back-plane  212 . Personal computer  226  may be located on yet another floor of the house. 
   Referring now to  FIG. 3B , there is illustrated an embodiment of the present invention illustrating a system  300  for measuring the acoustic quality of an end-point CPE  316  (wireless HUB). System  300  comprises a measurement device  310 , a model of a substantially ideal communications network  314 , end-point CPE  316 , a land-line analog phone  318 , an acoustic measurement stand  320 , and a test signal generator  312 . Although system  300  comprises a wireless HUB as CPE  316 , other embodiments may comprise any number of CPEs, such as a cellular telephone. Further, land-line phone  318  may be any device known in the art that is capable of transmitting an acoustic response to measurement stand  320 , such as a cellular telephone. Acoustic measurement stand  320  may be any type of suitable acoustic microphone stand known in the art. Moreover, measurement device  310  may be, but is not limited to, a personal computer, laptop, workstation, or other suitable measurement device. Measurement device  310 , may, for example, be a Microtronix™ IP-II. Moreover, a test signal generator may be any device capable of generating electronic signals for purposes of testing acoustic quality of components in a communications network. Also, network model  314  may be any software or hardware device capable of emulating an acoustic signal (such as a CDMA signal) for purposes of testing an end-point CPE. The network model may, for example, be a CMU-200 CDMA wireless network simulator manufactured by Tetronix™ that simulates a distortionless communications network. Other devices can be used to model a communications network that offer functionality similar to that of the CMU-200, which itself is one of various flavors of devices. 
   In operation, test signal generator  312  transmits an analog RF signal to network model  314 . Network model  314  converts the received analog signal from test signal generator  312  into a digital acoustic signal and transmits the acoustic signal to HUB  316  via a wire line coupled to a port of HUB  316 . HUB  316  transmits the acoustic signal to analog phone  318 . Assuming analog phone  318  has been previously tested and has an acceptable acoustic quality, the acoustic signal may be measured by acoustic measurement stand  320 . Measurement stand  320  transmits an indication of acoustic quality to measurement device  310 . Measurement device  310 , using the data acquired by the indication of acoustic quality, measures any number of acoustic parameters. The acoustic parameters include, but are not limited to, a receive frequency response, to analyze the voice quality received by the wireless HUB  316 ; a transmit frequency response, to analyze the voice quality transmitted by the wireless HUB  316 ; and a sidetone frequency response, to check the sidetone levels of the wireless HUB  316 . Measurement device  310  may present this data to a user in graphical form on a presentation device  310 A. Although system  300  illustrates test signal generator  312  and measurement device  310  as separate devices, generator  312  and device  310  may be incorporated into one device. Exemplary results using system  300  are illustrated in  FIGS. 4A through 4C . 
   Referring in combination to  FIGS. 4A-4C , there are illustrated in graphical form transmit, receive, and sidetone frequency responses for an exemplary system, such as system  300  illustrated in  FIG. 3B . The end-point CPE being evaluated was a CDMA HUB, manufactured by Tellular™. Testing of the CDMA HUB was performed using a sine wave test signal. Testing could also be accomplished using a TSG-C SWG 4.1 EAAH test signal ( FIGS. 5A-5B ). The latter produces more repeatable results for CDMA end-point CPEs because the codecs used are better adapted for CDMA devices. 
   Referring now to  FIGS. 4A and 4B , there are illustrated lines  410  and  412 , which set boundaries for transmit and receive frequency responses of a wireless communication device. Boundaries  410  and  412  are determined by the Telecommunications Industry Association (TIA) requirements. Raw data received by acoustic measurement device  320  and indicated to measurement device  310  is illustrated by a line  416 . Using a band average technique, common in the industry, data received by measurement device  310  is averaged together into line  414 .  FIGS. 5A and 5B  illustrate exemplary transmit and receive frequency responses using the aforementioned TSG-C SWG 4.1 EAAH test signal. The band average technique is not used because the variance of raw data illustrated by lines  510  and  512  in  FIGS. 5A and 5B  are not as great as in  FIGS. 4A and 4B . As is illustrated in  FIGS. 4A and 4B , the transmit and receive frequency response of the CDMA HUB is well within industry standard limits as determined by the TIA. Further, the TIA standard for send loudness response (SLR) is 8+/−3 dB and the requirement for the receive loudness response (RLR) is 2+/−3 dB. As can be seen in  FIGS. 4A and 4B , the SLR and RLR parameters are within industry standards. Referring to  FIG. 4C , there is shown a sidetone frequency response  418 . As determined by industry standards, a sidetone masking rating (STMR) of 2.40 is well within industry standards. 
   Referring now to  FIG. 6 , there is illustrated an embodiment of a method  600  for measuring the acoustic quality of HUB  316  of system  300 . Method  600  begins at a step  610  with the transmission of a test signal (either sinusoidal or EAAH) by test signal generator  312  to network model  314 . At a step  612 , network model  314  outputs a substantially distortionless acoustic signal (such as a CDMA signal) to end-point CPE  316 . At a step  614 , the acoustic signal is received by CPE  316 . At a step  616 , the acoustic signal is transmitted to analog phone  318 , which outputs an indication of acoustic quality to measurement stand  320 . Measurement device  310  receives the indication of acoustic quality from measurement stand  320  and analyzes the indication to measure any number of acoustic parameters. Finally, at a step  618 , data representing acoustic quality is presented on presentation device  310 A. 
   Embodiments of the present invention are intended in all respects to be illustrative rather than restrictive. Alternative embodiments will become apparent to those skilled in the art that do not depart from its scope. Many alternative embodiments exist but are not included because of the nature of this invention. A skilled programmer may develop alternative means of implementing the aforementioned improvements without departing from the scope of the present invention. 
   It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations and are contemplated within the scope of the claims. Not all steps listed in the various figures need be carried out in the specific order described.