Abstract:
Embodiments of the present invention relate to an improved man-machine interface for an apparatus. The interface comprises at least one graphical representation of a controllable parameter.

Description:
FIELD OF THE INVENTION 
       [0001]    Embodiments of the invention relate to an apparatus and method of control thereof. 
       BACKGROUND TO THE INVENTION 
       [0002]    Referring to  FIG. 1 , there is shown an embodiment of a front panel  100  of digital RF signal generator. The front panel  100  corresponds to that of a 3410 Series Digital RF Signal Generator available from Aeroflex International Limited. The 3410 Series Digital RF Signal Generator manual, document part no. 46892/499, which is incorporated herein by reference, is also available from Aeroflex International Limited. 
         [0003]    The front panel  100  comprises a standby/on switch  101 , an RF output  102  in the form of a 50Ω N-type socket, an external Q input or external frequency modulation input  103  and an I input or external amplitude modulation input  104 . The front panel  100  also comprises a touch-sensitive display  106  and a keyboard  108 . 
         [0004]      FIG. 2  shows an expanded view  200  of the keyboard  108 . It can be appreciated that the keyboard  108  comprises navigation keys  202 , function keys  204 , a numeric keypad  206 , terminator keys  208 , output control and diagnostic keys  210  and increment/decrement keys and a rotary control  212 . The function and operation of each of the above are described in detail in the above referenced document. 
         [0005]    A function is initially selected using the touch-sensitive display  106  either on a function label or by selecting a parameter value of interest. It is possible to select functions using their corresponding keys on the keyboard  108 , the numeric keypad  206  or the rotary control  215 . 
         [0006]    The numeric keys are used to set parameters to specific values, which can be varied in steps of any size using the “×10”  214  and “÷10”  216  keys and/or the rotary control  215 . The “×10”  214  and “÷10”  216  keys are used to adjust the rotary control sensitivity or resolution. 
         [0007]    A development of the man-machine interface of digital RF signal generators sought to simplify its physical characteristics. The simplification provided a larger touch-sensitive screen and displayed keyboards, rotary controls and the like on the touch-sensitive screen instead of providing physical keys and rotatable knobs. 
         [0008]    For example, the 6413A UMTS (3G) Base Station Test System also available from Aeroflex International Limited comprises a front panel  300  that has a large touch-sensitive screen  302  as can be appreciated from  FIG. 3 . The touch-sensitive screen  302  is used to provide an intuitive man-machine interface such that all functions of the test system can be accessed and controlled. Of particular interest is the graphical rotary control  304 , which is operable in a manner that is substantially identical to the rotary control  215  described with reference to  FIGS. 1 and 2 . 
         [0009]    However, it has been found that it can be difficult to enter certain categories of parameters using rotary controls, in particular using software realised rotary controls. 
         [0010]    In particular, without a physical rotary control present, it is difficult to move one&#39;s finger in a circle using a touch screen as there is no physical wheel to guide your finger. Furthermore, it is very difficult to move one&#39;s finger quickly to modify a value by large amounts quickly for the same reason. Still further, there is very little feedback regarding how much a finger needs to be moved to effect a desired modification to the parameter or value of interest. 
         [0011]    It is an object of embodiments of the invention to at least mitigate one or more problems of the prior art. 
       SUMMARY OF EMBODIMENTS OF THE INVENTION 
       [0012]    Accordingly, embodiments of the invention provide an apparatus as claimed in claim  1 . 
         [0013]    Advantageously, embodiments of the invention support making adjustments to numerical values. Particular embodiments support making such adjustments to such numerical values having a certain category of dynamic range such as, for example, a large dynamic range. Still further, such adjustments can be realised preferably without requiring a user to enter the entire numerical value using a numeric keypad. 
         [0014]    Embodiments of the present invention advantageously allow a finger, stylus or other integer to move in a substantially straight line, which means that it is much easier to control the apparatus, that is, to vary the parameter. Furthermore, while there is an absence of feedback in the case of a rotary control, the indicia on one or more of the sliders provide an indication of the current value of the numerical value or parameter, which, in turn, allows one to appreciate by how much the parameter has changed or has to change before a target or desired value is reached. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0015]    Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings in which: 
           [0016]      FIG. 1  shows a first prior art signal generator; 
           [0017]      FIG. 2  depicts a more detailed view of the prior art signal generator of  FIG. 1 ; 
           [0018]      FIG. 3  illustrates a prior art test system; 
           [0019]      FIG. 4  shows an apparatus according to an embodiment; 
           [0020]      FIGS. 5 to 13  depict various pairs of sliders according to respective embodiments; 
           [0021]      FIG. 14  illustrates a flowchart showing processing steps according to an embodiment of the invention; 
           [0022]      FIG. 15  shows a screen-display according to an embodiment; and 
           [0023]      FIG. 16  shows a screen-display according to an embodiment. 
       
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
       [0024]      FIG. 4  shows a schematic representation of an apparatus  400  according to an embodiment of the invention, which is preferably realised as an embedded PC. The apparatus comprises a CPU  402  for executing software used in realising the embodiment of the invention. The software is stored in memory, such as, for example, ROM/RAM,  404  as is well understood within the art of embedded PCs for execution by the CPU  402 . The CPU  402  is connected to a memory controller hub (MCH)  406  that manages the interactions with the other chips forming the apparatus. The MCH  406  is coupled to the memory  404  and to a graphics controller  408 . The graphics controller  408  controls the operation of the screen  410 . In the present embodiment the screen is a touch-sensitive screen. The MCH  406  is coupled to a south-bridge or I/O controller hub (ICH)  412 . One skilled in the art appreciates that embodiments realised using a touch-sensitive display comprise a touch-sensitive membrane or overlay  413 ′ coupled with a touch-screen controller and driver  413 ″. The touch-screen controller and driver converts presses into events that the system can use. The ICH  412  is connected to various I/O subsystems  414  and to a BIOS  416 . The detailed structure, chipset and operation of the above will not be described because they are familiar to one skilled in the art. 
         [0025]    Images or graphical outputs/representations (not shown) depicted on the display  410  are generated by the graphics controller such as, for example, an AGP Intel 740 or some other display controller resident in the AGP. 
         [0026]    The software is arranged to present a pair of sliders  500 , which, as can be seen in  FIG. 5 , are graphically represented on the touch-sensitive display  410 . The pair of sliders  500  comprises a first slider  502  and a second slider  504 . The first slider  502  is used to represent a first portion of a numerical value or parameter to be controlled or varied in response to user input such as, for example, an integer portion. The second slider  504  is used to represent a second portion of the numerical value or parameter to be controlled or varied in response to user input such as, for example, a fractional or decimal portion. In preferred embodiments, the numerical value will be stored in memory or some other form of storage such as a register. Preferably, the numerical value or parameter is used to influence the generation or analysis of a physical signal such as for example a signal having a particular characteristic that is governed by the numerical value. The particular characteristic can be one or more of frequency, voltage amplitude, current amplitude, modulation type, modulation index, time such as Capture time or Capture length, measurement span, sample rate, graphical marker position in frequency or time. One skilled in the art appreciates that the embodiments of the invention can be used to control any numerical value. The I/O subsystem is used to produce physical manifestations of signals according to the numerical value or parameter. Embodiments of the invention can be used to modify the value in terms of integer and decimal parts, real and imaginary parts, I and Q parts of a signal, exponent and mantissa parts. Furthermore, in terms of coordinates, the slider could be used to set or modify one or more coordinates, preferably simultaneously. 
         [0027]    It can be appreciated that the first slider  502  comprises a number of ticks such as, for example, the first tick  506  from the left. The ticks have associated values and units. The units can represent units of measurement or units of control. For example, the first tick  506  has an associated value of “7”  508  and an associated unit of milliseconds  510 . The same applies to the other ticks shown on the first slider  502 . It can be appreciated that the first slider  502  depicts a portion of a current dynamic range of the numerical value or parameter to be controlled starting with a displayed lower bound and finishing with a displayed upper bound. The slider depicts a small portion of the overall dynamic range of the numerical value or parameter. It will be appreciated, however, that the bounds of the slider are not the same as the upper and lower bounds of the parameter in general. However, one skilled in the art will appreciate that the displayed upper and lower bounds are merely illustrative and do not represent the full dynamic range over which the numerical value or parameter can be controlled or varied. 
         [0028]    Similarly, the second slider  504  comprises a number of ticks or graduations representing the decimal or fractional part of the numerical value or parameter being controlled, varied or set. 
         [0029]    In the illustrated embodiment, the slider depicts a numerical value of exactly 9 ms as can be appreciated from the central indicator bar  512 . 
         [0030]    In the case of a touch-sensitive display, if a finger or stylus is moved left or right on an area of the overlay  413 ′ corresponding to one of the sliders  502  or  504 , the graphical depiction of the numerical value moves correspondingly. Therefore, for example, moving the first slider  502  left will increase the numerical value or parameter. Moving the first slider  502  right will reduce the numerical value or parameter. 
         [0031]    Releasing a currently actuated slider, that is, lifting the finger or stylus, will cause the tick of the slider that is nearest to the indicator bar  512  to snap to that indicator bar thereby aligning the tick with the indicator bar  512 . 
         [0032]    Embodiments can be realised in which the slider movement progressively slows down following release before snapping into alignment with the indicator bar. 
         [0033]    It will be appreciated that the numerical values represented by the ticks of the second slider  504  are arranged to wrap around and span upper and lower bounds, that is, have a dynamic range, dictated by the units of the first slider  502 . In general, moving the slider  504  left will increase the numerical value or parameter and moving the slider  502  right will decrease the numerical value or parameter. 
         [0034]      FIGS. 6 to 8  illustrate how to set the numerical value or parameter to 10.312 ms given a current value of 9 ms. Referring to  FIG. 6 , it can be appreciated that the first slider  502  has been moved left such that the tick  600  associated with 10 ms value is nearest the indicator bar  512  when the slider is released or no longer being actuated by the user.  FIG. 7  shows the tick  600  associated with the 10 ms value having snapped to the indicator bar  512 .  FIG. 8  shows the second slider  504  as having been moved such that the tick associated with 0.312 ms has snapped into alignment with the indicator bar  512 . Therefore, the numerical value or parameter will take on the value 10.312 ms. 
         [0035]    A further embodiment of the invention can be realised in which increment and decrement functions are associated with one or more of the sliders. Referring to  FIG. 9 , there is shown a pair of sliders  900 . A first slider  902  of the pair  900  has associated first  904  and second  906  buttons. The first button  902  has an associated increment function. The second button  906  has an associated decrement function. The second slider  908  also has an associated pair of increment and decrement buttons/functions  910  and  912 . One skilled in the art will appreciate that the increment and decrement buttons are embodiments of actuable devices. 
         [0036]    The increment and decrement buttons and associated functions serve the purpose of allowing the units to be changed. In a preferred embodiment, the increment and decrement buttons vary the scale of their associated sliders. For example, the increment button  904  will increase the scale of the first slider  902  by a predetermined amount or in a predetermined manner. Embodiments can be realised in which the increase in scale corresponds to a factor of 10 increase. However, embodiments are not limited to such a multiplicative factor or, indeed, to multiplicative increases. Embodiment can be realised in which some other factor or increase in scale is used. Similarly, the decrement button  906  will decrease the scale of the first slider  902  by a predetermined amount or in a predetermined manner. Embodiments can be realised in which the decrease in scale corresponds to a factor of 10 decrease. However, embodiments are not limited to such a multiplicative factor. Embodiments can be realised in which some other factor or decrease in scale is used.  FIG. 10  illustrates the pair  900  of sliders in which the scale of the first slider  902  has been increased by a factor of 10.  FIG. 11  depicts the pair of sliders  900  with the second slider  908  having had its scale decreased by a factor of 10 from 0.01 resolution to 0.001 resolution. 
         [0037]    It will be appreciated that the dynamic ranges of the sliders might be varying according to intended capabilities of the apparatus such as, for example, maximum signal amplitude, current etc. Therefore, embodiments can be realised in which the ticks shown on the sliders are only depicted for values that fall within the dynamic range of the numerical value, parameter or signal characteristic being controlled.  FIGS. 12 and 13  shows respective sliders  1200  and  1300  depicting an absence of ticks beyond the upper and lower bounds of the parameter being controlled or varied on reaching the upper or lower limit of the dynamic range. 
         [0038]      FIG. 14  depicts a flowchart  1400  showing the processing steps undertaken by an apparatus according to an embodiment of the present invention. The software can be used to implement a method according to the flowchart  1400 . 
         [0039]    At step  1402 , graphical depictions of the sliders are initialised and displayed. The initialisation process comprises accessing data governing the initial settings of the sliders such as, for example, the units and resolution of the scales, the upper and lower bounds of the scale and the initial parameter value. The sliders are realised as respective windows and are displayed when a numerical value is selected, which will be described in greater detail with reference to  FIGS. 15 and 16 . 
         [0040]    The apparatus enters a loop in which repeated determinations are made regarding whether or not an input has been detected. Alternatively, embodiments can be realised that are interrupt driven such that actuating the touch-sensitive screen raises an interrupt that is serviced by steps  1404  onwards of the flowchart  1400 . 
         [0041]    A determination is made, at step  1404 , regarding whether or not an input has been detected. If the determination is negative, control returns to step  1404 . If the determination is positive control passes to step  1406 . 
         [0042]    Step  1406  determines if the input relates to a slider or an increment/decrement button. If the determination is that the input relates to a slider, processing continues at step  1408 , otherwise the input is assumed to relate to an increment or decrement button of one of the sliders, whereupon processing moves to step  1410 . 
         [0043]    If it is established, at step  1406 , that the input relates to a slider, an assessment is made, at step  1408 , regarding whether or not the input relates to the first slider. If the assessment at step  1408  is positive, a first portion, such as, for example, the integer part, of the numerical value or parameter is adjusted according to the degree and direction of movement of the slider, that is, according to slider actuation, at step  1412 . 
         [0044]    If the assessment, at step  1408 , is negative, it is assumed that the input relates to the second slider and processing continues at step  1414  where a second portion, such as, for example, the fractional or decimal part, of the numerical value or parameter is adjusted according to the degree and direction of slider actuation. Processing then resumes at step  1404 . 
         [0045]    Returning to step  1410 , an assessment is undertaken to determine if the increment button associated with the first slider has been actuated. If that assessment is positive, the scale of the first slider is varied, that is, increased in a predetermined manner at step  1416  and processing then resumes at step  1404 . 
         [0046]    If the assessment at step  1410  is negative, a determination is made, at step  1418 , regarding whether or not the input related to actuation of the first slider decrement button. If that determination is positive, the scale of the first slider is decreased in a predetermined manner at step  1420 . Thereafter processing resumes at step  1404 . 
         [0047]    If the determination at step  1418  is negative, an assessment is made regarding whether or not the input is associated with the increment button of the second slider at step  1422 . If the assessment at step  1422  is positive, the scale of the second slider is increased in a predetermined manner at step  1424  and processing thereafter resumes at step  1404 . 
         [0048]    If the assessment at step  1422  is negative, it is assumed that the input relates to the decrement button of the second slider and the scale of the second slider is varied accordingly at step  1426 . Thereafter processing resumes at step  1404 . 
         [0049]    Referring to  FIG. 15 , there is shown a screen display  1500  of an apparatus (not shown) according to an embodiment of the invention. The display  1500  comprises a number of graphs  1504  to  1510  for depicting power spectra, that is, power, measured in dBm, against frequency. The screen display  1500  also shows a plurality of buttons  1512  to  1524  that are used to set respective parameters and/or invoke, apply or perform various filters, functions or actions. The first button  1512  sets the minimum capture time for establishing the power spectrum of an input signal (not shown). The second button  1514  is used to select the type of reference mask to be applied to the signal after establishing the signals power spectrum. The reference mask, in the embodiment illustrated, is labelled “General” and can be used to implement any type of mask that is desired to be associated with the label “General”. The third button  1516  is used to set and/or specify the system bandwidth of the input signal of interest, which is currently set to 10 MHz. The fourth button  1518  is used to display or select a cell ID, which corresponds to a cell whose RF characteristics, power spectrum in this case, are under investigation. The fifth button  1520  is used to enable or disable tracking time, which is an algorithm that can be used to improve analysis quality of the signal of interest. The sixth button  1522  is used to toggle amplitude tracking on and off, which is an algorithm that can be used to improve analysis quality of the signal of interest. The seventh button  1524  is used to toggle phase tracking on and off, which is an algorithm that can be used to improve analysis quality of the signal of interest. 
         [0050]    The current centre frequency of the power spectrum to be determined is displayed in a corresponding field or window  1526  with an adjacent “Adjust” button  1528 . Invoking the “Adjust” button  1528  displays a pair of sliders according to embodiments of the present invention that can be used to adjust the centre frequency of the power spectrum of interest. One slider adjusts the integer portion of the centre frequency while the other slider adjusts the decimal portion of the frequency. Similarly, a trigger power level is displayed in a corresponding field or window  1530  that also has a corresponding “Adjust” button  1532 , which is used to adjust the power level at which the apparatus triggers. The triggering mode is displayed and selectable in a toggling manner by actuating a triggering button  1534 . The sampling is started and stopped using a start/stop button  1536 . 
         [0051]    The display also shows three further buttons. The first of the three further buttons is a window movement button  1538 , which, when actuated, is used to move a respective window in a drag and drop manner. The second button  1540  of the three is a used to minimise or maximise the window and the final button  1542  is used to close the window. 
         [0052]    Referring to  FIG. 16  there is shown the above screen display  1500  in which the “Min Capture Time” button  1512  has been actuated, which has resulted in a pair of sliders  1600  according to an embodiment of the present invention to be displayed. The pair of sliders  1600  comprise a first slider  1602  and a second slider  1604  that are respectively used to set the first and second portions such as, for example, integer and decimal parts, of the minimum period of time over which the power spectrum should be captured. It can be appreciated that the pair of sliders also comprises three additional buttons  1606  to  1610  that are used to position and size the window containing the pair of sliders  1600  in a manner substantially identical to that described above with respect to  FIG. 15 . The three additional buttons comprise a window position or movement button  1606  that can be used to change the position of the pair of sliders  1600  in a drag and drop manner. The second button  1608  of the three is a used to minimize or maximise the window and the final button  1610  is used to close the window. 
         [0053]    The above embodiments have been described with reference to using a finger or stylus to control the movement of the slider and hence control the underlying numerical value or parameter represented by the slider. However, embodiments are not limited thereto. Embodiments can be realised in which some other input device is used to control the slider such as, for example, a mouse, which would be connected via the I/O subsystem  414 . 
         [0054]    Although the above embodiments have been described with reference to the units of measurement or physical entity being time and, more particularly, milliseconds, embodiments are not limited thereto. Embodiments can equally well be realised that use some other units of time or some other physical quantity such as, for example, units of frequency, units of voltage, units of current, modulation index, time such as Capture time or Capture length, measurement span, sample rate, graphical marker position in frequency or time. However, one skilled in the art appreciates that embodiments of the invention can be used to set or control any parameter. 
         [0055]    The above embodiments have been described with reference to a digital signal generator. However, embodiments are not limited thereto. Embodiments can be realised using other apparatuses in which there is a desire to control a parameter. For example, embodiments can be used in relation to an oscilloscope, a spectrum analyser, Radio Test set, Radio test system or measurement system of any type, Vector signal Analysis, Vector Signal Generator and the like. 
         [0056]    Embodiments have been described with reference to the numerical value or parameter representing or being associate with a corresponding physical characteristic of a signal. However, embodiments are not limited to such arrangements. Embodiments can be realised in which the numerical value or parameter controls a process. For example, if the parameter represents time, the sliders might be used to control the sampling period or frequency of an ND converter. Embodiments can be realised in the context of graphical scaling where the number entered affects a current scale of a graph. Furthermore, embodiments can be realised in the context of marker movement, where the number entered affects the location of a marker and, therefore, the displayed value of the marker. 
         [0057]    The above embodiments have described with reference to the sliders using ticks. However, embodiments are not limited thereto. Embodiments can be realised in which some other indicia are used. 
         [0058]    Although two sliders have been used in the above embodiments of the invention, embodiments can be realised in which some other number, that is, one or more, of sliders can be used in embodiments of the invention such as specifying coordinates in terms of X, Y and Z values simultaneously, or three levels of precision, such as a slider for the integer part of the value, a slider specifying up to 5 decimal places, and a slider specifying more than 5 decimal places. One skilled in the art appreciates that the flow chart shown in and described with reference to  FIG. 14  can be suitably varied according to the number of graphical depictions, such as sliders, used to realise an embodiment 
         [0059]    It will be appreciated that embodiments of the present invention can be realised in the form of hardware, software or a combination of hardware and software. Any such software may be stored in the form of volatile or non-volatile storage such as, for example, a storage device like a ROM, whether erasable or rewritable or not, or in the form of memory such as, for example, RAM, memory chips, device or integrated circuits or on an optically or magnetically readable medium such as, for example, a CD, DVD, magnetic disk or magnetic tape or the like. It will be appreciated that the storage devices and storage media are embodiments of machine-readable storage that are suitable for storing a program or programs comprising instructions that, when executed, implement embodiments of the present invention. Accordingly, embodiments provide a program comprising code for implementing a system or method as claimed in any preceding claim and a machine readable storage storing such a program. Still further, such programs may be conveyed electronically via any medium such as a communication signal carried over a wired or wireless connection and embodiments suitably encompass the same.