Author: claimsbot

1. An apparatus for estimating a channel in a Broadband Wireless Access (BWA) communication system, comprising:
a subcarrier demapper for extracting pilot symbols at preset positions for a channel estimation;
a channel estimator for acquiring channel estimate values of subcarriers through an Infinite Impulse Response (IIR) filtering using the pilot symbols provided from the subcarrier demapper and a preset filter factor value based on changes in the channel condition; and
a filter factor selector for selecting an optimal filter factor required for the IIR filtering per frame among a plurality of pre-classified filter factors using the pilot symbols provided from the subcarrier demapper,
wherein the channel estimator performs the IIR filtering using the filter factor selected by the filter factor selector, instead of the preset filter factor,
wherein the filter factor selector estimates a channel estimate value of a preamble, estimates a channel estimate value of a first symbol by applying the IIR filtering using symbols after the preamble with respect to each of the pre-classified filter factors, measures an error accumulation value which accumulates errors between the preamble and the estimated first symbol for each of the pre-classified filter factor, measures a moving average which averages the error accumulation values during a preset number of frames with respect to each of the pre-classified filter factors, and provides a filter factor of the smallest moving average among the measured moving averages to the channel estimator.
2. The apparatus of claim 1, wherein the filter factor selector estimates the channel estimate value of the first symbol using the symbols after the preamble with respect to each of the pre-classified filter factors based on the following equation:
1(l)=(1\u2212\u03b3j)H2(l)+\u03b3jH1(l),
where Hi(j) denotes a j-th subcarrier estimate value of an i-th symbol index, i(j) denotes an IIR-filtered channel estimate value for the j-th subcarrier of the i-th symbol index, and \u03b3j denotes a j-th filter factor of classified filter factor candidates.
3. The apparatus of claim 1, wherein the filter factor selector measures the error accumulation value which accumulates the errors between the preamble and the estimated first symbol with respect to each of the pre-classified filter factors based on the following equation:
\u03b4

j
\u2061

(
n
)
=
\u2211
k

\u2062
\u2062
\uf603
H
0

\u2061

(
k
)
–
H
1
j

\u2061

(
k
)
\uf604

2
,
where \u03b4j(n) denotes an error accumulation value of an n-th frame when the j-th filter factor \u03b3j of the classified filter factor candidates is used, H0(k) denotes a channel estimate value for a k-th subcarrier of the preamble, and H1j(k) denotes a channel estimate value for the k-th subcarrier of the first symbol.
4. The apparatus of claim 3, wherein the filter factor selector accumulates only errors corresponding to pilot subcarrier positions of the first symbol to measure the error accumulation value which accumulates the errors between the preamble and the estimated first symbol with respect to each of the pre-classified filter factors.
5. The apparatus of claim 1, wherein the filter factor selector measures the moving average which averages the error accumulation values during a preset number of frames with respect to each of the pre-classified filter factors based on the following equation:
\u0394
j

=
1
N

\u2062

(
\u03b4

j
\u2061

(
n
)
+

\u03b4

j
\u2061

(

n
–
1

)
+
\u2026
+

\u03b4

j
\u2061

(

n
–
N
+
1

)
)
,
where \u0394j denotes a moving average when the j-th filter factor \u03b3j is used among the classified filter factor candidates, N denotes a number of recent frames preset to measure the moving average, and \u03b4j(n) denotes an error accumulation value of the n-th frame using \u03b3j.
6. A method for estimating a channel in a Broadband Wireless Access (BWA) communication system, the method comprising the steps of:
estimating channels of preamble subcarriers when a frame is received;
estimating subcarrier estimate values of a neighbor symbol through a time-axis interpolation;
Infinite Impulse Response (IIR)-filtering the subcarriers estimated through the time-axis interpolation using a preset filter factor value based on changes in the channel condition;
estimating channels of all of subcarriers of a symbol index through a frequency-axis interpolation using the filtered subcarrier estimate values; AND
selecting an optimal filter factor required for the IIR filtering among a plurality of pre-classified filter factors,
wherein the IIR filtering uses the selected filter factor instead of the preset filter factor,
wherein the optimal filter factor selecting comprises:
estimating a channel estimate value of a first symbol using symbols after the preamble with respect to each of the pre-classified filter factors by applying the IIR filtering;
measuring error accumulation values which accumulate errors between the preamble and the estimated first symbol with respect to each of the pre-classified filter factors;
measuring moving averages which average the error accumulation values during a preset number of frames with respect to each of the pre-classified filter factors; and
selecting a filter factor of the smallest moving average among the measured moving averages as the optimal filter factor.
7. The method of claim 6, wherein the channel estimate value of the first symbol using the symbols after the preamble with respect to each of the pre-classified filter factors is estimated by applying the IIR filtering based on the following equation:
1(l)=(1\u2212\u03b3j)H2(l)+\u03b3jH1(l),
where Hi(j) denotes a j-th subcarrier estimate value of an i-th symbol index, i(j) denotes an IIR-filtered channel estimate value for the j-th subcarrier of the i-th symbol index, and \u03b3j denotes a j-th filter factor of classified filter factor candidates.
8. The method of claim 6, wherein the error accumulation value which accumulates the errors between the preamble and the estimated first symbol with respect to each of the pre-classified filter factors is measured based on the following equation:
\u03b4

j
\u2061

(
n
)
=
\u2211
k

\u2062
\u2062
\uf603
H
0

\u2061

(
k
)
–
H
1
j

\u2061

(
k
)
\uf604

2
,
where \u03b4j(n) denotes an error accumulation value of an n-th frame when the j-th filter factor \u03b3j of the classified filter factor candidates is used, H0(k) denotes a channel estimate value for a k-th subcarrier of the preamble, and H1j(k) denotes a channel estimate value for the k-th subcarrier of the first symbol.
9. The method of claim 8, wherein, when the error accumulation value which accumulates the errors between the preamble and the estimated first symbol with respect to each of the pre-classified filter factors is measured, the only errors corresponding to pilot subcarrier positions of the first symbol are accumulated.
10. The method of claim 6, wherein the moving average which averages the error accumulation values during a preset number of frames with respect to each of the pre-classified filter factors is measured based on the following equation:
\u0394
j

=
1
N

\u2062

(
\u03b4

j
\u2061

(
n
)
+

\u03b4

j
\u2061

(

n
–
1

)
+
\u2026
+

\u03b4

j
\u2061

(

n
–
N
+
1

)
)
,
where \u0394j denotes a moving average when the j-th filter factor \u03b3j is used among the classified filter factor candidates, N denotes a number of recent frames preset to measure the moving average, and \u03b4j(n) denotes an error accumulation value of the n-th frame using \u03b3j.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.

1. An operational system to control child safety locks on automobiles, comprising:
a) child safety locks, which prevents the rear doors of automobiles from being opened from the the inside when the child safety locks are engaged, see items 17 and 19 in FIG. 6 of drawings, which depicts child safety locks.
b) an electric motor, such as a solenoid, to move the child safety locks into the engaged or disengaged position.
c) an electronic display system, such as a light emitting diode, to indicate the status of the child safety lock mechanism, to show whether the child safety locks are engaged or disengaged.
e) circuit wires.
f) an electric motor is attached to each child safety lock, one end of the circuit wires is attached to each electric motor, the other end of the circuit wire is attached to the rocker arm switch.

1. A method comprising:
receiving status data indicating an error in connectivity between a device and a service provider;
processing the status data to determine a type of the error from among a plurality of types of errors;
selecting a first message to transmit to the device from among a plurality of stored messages using the type of the error, the first message prompting the user to provide information relating to the error;
transmitting the first message to the device;
receiving response data from the user in response to the first message, the response data providing the information relating to the error;
processing the response data to determine a diagnostic procedure to perform in response to the first message; and
performing the diagnostic procedure.
2. The method of claim 1, wherein the device comprises a telephonic device, and wherein transmitting the first message to the device comprises causing the first message to be played through a microphone of the telephonic device.
3. The method of claim 2, further comprising causing the telephonic device to ring before causing the first message to be played through the microphone.
4. The method of claim 3, further comprising:
while causing the telephonic device to ring, monitoring for an off-hook status of the telephonic device; and
after detecting the off-hook status, playing the first message over the telephonic device.
5. The method of claim 3, further comprising:
detecting whether the telephonic device is coupled to a voice port of the device; and
when the telephonic device is not coupled to the voice port of the device, providing a voice message indicator on a display output of the device.
6. The method of claim 1, further comprising:
after the diagnostic procedure, selecting a second message from among the plurality of stored messages based on an outcome of the diagnostic procedure; and
transmitting the second message to the device.
7. The method of claim 1, wherein:
determining the status of connectivity comprises performing a diagnostic analysis on a communications channel between the device and the service provider; and
selecting the first message comprises selecting the first message using the diagnostic analysis.
8. The method of claim 7, wherein the diagnostic analysis includes a spectrum analysis identifying a power density of communications channels across a frequency band over time.
9. The method of claim 1, further comprising:
receiving an update from the service provider, the update including an update to at least one feature of the device; and
in response to the update, transmitting a message to the device indicating the update is available.
10. A system comprising:
circuitry configured to:
receive status data indicating an error in connectivity between a device and a service provider;
process the status data to determine a type of the error from among a plurality of types of errors;
select a first message to transmit to the device from among a plurality of stored messages using the type of the error, the first message prompting the user to provide information relating to the error;
transmit the first message to the device;
receive response data from the user in response to the first message, the response data providing the information relating to the error;
process the response data to determine a diagnostic procedure to perform in response to the first message; and
perform the diagnostic procedure.
11. The system of claim 10, wherein the device further comprises a telephonic device, and wherein the circuitry is configured to cause the telephonic device to ring and the first message to be played through a microphone of the telephonic device.
12. The system of claim 11, wherein the circuitry is further configured to:
while causing the telephonic device to ring, monitor for an off-hook status of the telephonic device; and
after detecting the off-hook status, play the first message over the telephonic device.
13. The system of claim 11, wherein the circuitry is further configured to:
detect whether the telephonic device is coupled to a voice port of the device; and
when the telephonic device is not coupled to the voice port of the device, provide a voice message indicator on a display output of the device.
14. The system of claim 10, wherein the circuitry is further configured to:
after the diagnostic procedure, select a second message from among the plurality of stored messages based on an outcome of the diagnostic procedure; and
transmit the second message to the device.
15. The system of claim 10, wherein the circuitry is further configured to:
determine the status of connectivity by performing a diagnostic analysis on a communications channel between the device and the service provider; and
select the first message using the diagnostic analysis.
16. One or more computer-readable storage media having instructions stored thereon that, when executed by one or more processors, cause the one or more processors to implement operations comprising:
receiving status data indicating an error in connectivity between a device and a service provider;
processing the status data to determine a type of the error from among a plurality of types of errors;
selecting a first message to transmit to the device from among a plurality of stored messages using the type of the error, the first message prompting the user to provide information relating to the error;
transmitting the first message to the device;
receiving response data from the user in response to the first message, the response data providing the information relating to the error;
processing the response data to determine a diagnostic procedure to perform in response to the first message;
performing the diagnostic procedure;
selecting a second message from among the plurality of stored messages based on an outcome of the diagnostic procedure; and
transmitting the second message to the device.
17. The one or more computer-readable storage media of claim 16, wherein the device further comprises a telephonic device, and wherein the operations further comprise causing the telephonic device to ring and the first message to be played through a microphone of the telephonic device.
18. The one or more computer-readable storage media of claim 17, wherein the operations further comprise:
while causing the telephonic device to ring, monitoring for an off-hook status of the telephonic device; and
after detecting the off-hook status, playing the first message over the telephonic device.
19. The one or more computer-readable storage media of claim 17, wherein the operations further comprise:
detecting whether the telephonic device is coupled to a voice port of the device; and
when the telephonic device is not coupled to the voice port of the device, providing a voice message indicator on a display output of the device.
20. The one or more computer-readable storage media of claim 16, wherein:
determining the status of connectivity comprises performing a diagnostic analysis on a communications channel between the device and the service provider; and
selecting the first message comprises selecting the first message using the diagnostic analysis.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.

1. A polarization direction measuring apparatus comprising:
a first polarizing plate having an unknown polarization direction relative to a reference axis;
a sample whose a polarization direction is to be measured;
a rotatable sample holder on which the sample is mounted in a first direction and a second direction opposite to the first direction, wherein the sample holder rotates the sample along a reference axis in the azimuth direction;
a light source that generates light passing though the first polarizing plate and the sample; and
a light detector detecting light generated by the light source that passes though the first polarizing plate and the sample,
wherein the polarization direction of the sample is obtained by one half a difference between a first angle, at which the minimum quantity of light is detected when rotating the sample put in the first direction, and a second angle, at which the minimum quantity of light is detected when rotating the sample put in the second direction.
2. The polarization direction measuring apparatus of claim 1, wherein the sample is a second polarizing plate corresponding to the first polarizing plate.
3. The polarization direction measuring apparatus of claim 1, wherein the reference axis is perpendicular to a reference plane of the sample holder.
4. The polarization direction measuring apparatus of claim 1, wherein the sample holder includes:
a housing into which the sample is inserted;
a first insertion opening that is positioned at one side of the housing and fastens the sample inserted in the first direction; and
a light transmissive opening passing through the housing that transmits light passing through the first polarizing plate.
5. The polarization direction measuring apparatus of claim 4, wherein the sample holder further includes a second insertion opening with a shape that is symmetrical to the shape of the first insertion opening, the second insertion opening fastening the sample inserted in the second direction.
6. The polarization direction measuring apparatus of claim 4, wherein the sample holder further includes a grip positioned at a side of the housing that rotates the housing.
7. The polarization direction measuring apparatus of claim 1, wherein the light source is a laser light source.
8. The polarization direction measuring apparatus of claim 1, wherein the light detector includes one of a photodetector and a luminance meter.
9. A method of measuring a polarization direction comprising:
aligning a light source, a first polarizing plate, and a light detector;
inserting a sample into a sample holder in a first direction, wherein a reference axis of the sample holder aligns with the light source and the light detector;
rotating the sample holder in an azimuth direction to measure a first angle at which a minimum quantity of light is detected;
inserting the sample into the sample holder in a second direction opposite to the first direction;
rotating the sample holder in the azimuth direction to measure a second angle at which a minimum quantity of light is detected; and
obtaining a value corresponding to one half a difference between the first angle and the second angle to measure a polarization direction of the sample
wherein putting the sample in the first direction includes fastening the sample into an insertion opening of the sample holder in the first direction and inserting the sample in the second direction and fastening the sample into the insertion opening of the sample holder in the second direction.
10. The method of claim 9, wherein the sample is a second polarizing plate corresponding to the first polarizing plate.
11. The method of claim 9, wherein when inserting the sample in the first direction and the second direction, the sample holder is aligned between the first polarizing plate and the light detector.
12. The method of claim 9, wherein in aligning the light source, the first polarizing plate, and the light detector, a polarization direction of the first polarizing plate is unknown.
13. The method of claim 9, wherein when putting the sample in the first direction, the reference axis is perpendicular to a reference plane of the sample holder.
14. The method of claim 9, wherein the light source is a laser light source.
15. The method of claim 9, wherein the minimum quantity of light in the first and second directions is detected using the light detector.
16. The method of claim 15, wherein the light detector includes one of a photodetector and a luminance meter.