Apparatus and method for alerting computer users in a wireless LAN of a service area transition
First Claim
1. A method for alerting a user of a mobile computer to a deteriorated communication condition between the mobile computer and a computer server linked to the mobile computer over a wireless link, the method comprising the steps of:
- (1) calculating a packet transmission error rate, said calculating step comprising the steps ofa. transmitting, from the mobile computer to the computer server, a plurality of Link Quality Test (LQT) packets;
b. receiving the transmitted LQT packets at the computer server;
c. determining whether an error-free reception of each received LQT packet occurred;
d. transmitting an acknowledgment packet from the computer server to the mobile computer in response to each error-free reception; and
e. calculating said packet transmission error rate in the mobile computer as a function of the number of acknowledgment packets received from the computer server;
(2) comparing the packet transmission error rate in the mobile computer with a threshold value to determine whether the deteriorated communication condition exists, and(3) indicating to the user, responsive to the determination that the packet transmission error rate exceeds the threshold value in said step (2), the deteriorated communication condition.
1 Assignment
0 Petitions
Accused Products
Abstract
An apparatus and method is provided for detecting when a mobile computer linked to a computer server over a wireless link is about to move out of the range of the LAN and for alerting the computer user before the communication link with the computer server becomes severely deteriorated. According to the apparatus and method, a predetermined number of data packets are periodically transmitted from the mobile computer to the computer server, and the number of data packets successfully transmitted is determined based on acknowledgments received from the computer server, preferably using a cyclical redundancy check (CRC) code in the transmitted packets. Based on the number of data packets successfully transmitted, a transmission error rate is computed. The error rate is compared to a threshold value and, if the threshold is exceeded, an indication is provided to the user that the communication quality is deteriorating. Parameters for controlling the number of predetermined packets, the time interval for repeating the transmissions, the method of indication, and the thresholds may be changed by the user to adapt to different requirements and environments. In a preferred embodiment, transmission of the predetermined number of data packets is inhibited if communication has been made with the computer server during a predetermined time interval, thereby improving efficiency. Additionally, a background error rate may be computed from which one or more threshold values are adjusted in order to adapt to noisy environments.
-
Citations
30 Claims
-
1. A method for alerting a user of a mobile computer to a deteriorated communication condition between the mobile computer and a computer server linked to the mobile computer over a wireless link, the method comprising the steps of:
-
(1) calculating a packet transmission error rate, said calculating step comprising the steps of a. transmitting, from the mobile computer to the computer server, a plurality of Link Quality Test (LQT) packets; b. receiving the transmitted LQT packets at the computer server; c. determining whether an error-free reception of each received LQT packet occurred; d. transmitting an acknowledgment packet from the computer server to the mobile computer in response to each error-free reception; and e. calculating said packet transmission error rate in the mobile computer as a function of the number of acknowledgment packets received from the computer server; (2) comparing the packet transmission error rate in the mobile computer with a threshold value to determine whether the deteriorated communication condition exists, and (3) indicating to the user, responsive to the determination that the packet transmission error rate exceeds the threshold value in said step (2), the deteriorated communication condition. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
-
-
12. Apparatus for alerting a user of a mobile computer to a deteriorated communication condition between the mobile computer and a computer server linked to the mobile computer over a wireless link, the apparatus comprising:
-
calculating means for calculating a packet transmission error rate, said calculating means comprising first transmitting means for transmitting, from the mobile computer to the computer server, a plurality of Link Quality Test (LQT) packets; receiving means for receiving the transmitted LQT packets at the computer server; first comparing means for determining whether an error-free reception of each LQT packet occurred; second transmitting means for transmitting an acknowledgment packet from the computer server to the mobile computer in response to the error-free reception of each LQT data packet; and computing means in the mobile computer for calculating said packet transmission error rate as a function of the number of acknowledgment packets received from the computer server; second comparing means for comparing the packet transmission error rate with a threshold value to determine whether the deteriorated communication condition exists, and indicating means for indicating to the user, responsive to the determination that the packet transmission error rate exceeds the threshold value, the deteriorated communication condition. - View Dependent Claims (13, 14, 15, 16, 17, 18, 19, 20, 21, 22)
-
-
23. Apparatus for alerting a user of a mobile computer to a deteriorated communication condition between the mobile computer and a computer server linked to the mobile computer over a wireless link, comprising:
-
transmitting means for transmitting a predetermined number of LQT packets from the mobile computer to the computer server; receiving means for receiving acknowledgments from the computer server, said acknowledgements corresponding to one or more of said predetermined number of LQT packets transmitted by said transmitting means; determining means for determining whether any of the predetermined number of transmitted LQT packets was not acknowledged by the computer server; retransmitting means for retransmitting, responsive to said determining means, any LQT packets not acknowledged by the computer server; computing means for computing, based on the number of LQT packets acknowledged by the computer server, a transmission error rate; comparing means for comparing the transmission error rate with a predetermined threshold; and indicating means for indicating, responsive to the transmission error rate exceeding the predetermined threshold, an alert to the user representing the deteriorated communications condition. - View Dependent Claims (24, 25, 26, 27, 28)
-
-
29. A mobile computer, comprising:
-
a computer bus, a processor, coupled to the computer bus, having means for generating a plurality of link quality test (LQT) packets for transmission over a wireless link to a computer server and means for determining, responsive to the number of error-free acknowledgments received from the computer server for said generated LQT packets, the communications quality over the wireless link, a communications adapter, coupled to the computer bus, for modulating said generated LQT packets onto a radio frequency signal and transmitting said modulated LQT packets over said wireless link to said computer server, and for receiving and demodulating said acknowledgements from said computer server over said wireless link; and a communications quality indicator for indicating the communications quality to a user. - View Dependent Claims (30)
-
Specification