Data communication systems and methods

Abstract

A method for data communication includes determining that a downlink receiver is not receiving downlink data from a movable object based on a state of the downlink receiver, generating first synchronization information in response to determining that the downlink receiver is not receiving the downlink data from the movable object, transmitting uplink data to the movable object, and generating second synchronization information in response to completion of uplink data transmission. The first synchronization information is provided to the downlink receiver to prevent operation of the downlink receiver, and the second synchronization information is provided to the downlink receiver to allow operation of the downlink receiver.

What is claimed is: 
     
         1 . A method for data communication comprising:
 determining that a downlink receiver is not receiving downlink data from a movable object based on a state of the downlink receiver;   generating first synchronization information in response to determining that the downlink receiver is not receiving the downlink data from the movable object, the first synchronization information being provided to the downlink receiver to prevent operation of the downlink receiver;   transmitting uplink data to the movable object; and   generating second synchronization information in response to completion of uplink data transmission, the second synchronization information being provided to the downlink receiver to allow operation of the downlink receiver.   
     
     
         2 . The method of  claim 1 , wherein the uplink data includes control data to control the movable object and third synchronization information, wherein the third synchronization information is configured to synchronize data transmission with the movable object. 
     
     
         3 . The method of  claim 1 , further comprising:
 measuring one or more quality characteristics of each of a plurality of working frequency channels to determine measured quality characteristics; and   selecting a working frequency channel from the plurality of working frequency channels based on the measured quality characteristics.   
     
     
         4 . The method of  claim 3 , further comprising:
 receiving the downlink data from the movable object using the working frequency channel in response to the generated second synchronization information.   
     
     
         5 . The method of  claim 3 , wherein the one or more quality characteristics include at least one of noise, interference, signal-to-noise ratio (SNR), bit error rate, or fading rate. 
     
     
         6 . The method of  claim 1 , wherein the uplink data is encoded using a first coding scheme and the downlink data is encoded using a second different coding scheme. 
     
     
         7 . The method of  claim 1 , wherein the uplink data is modulated using a first modulation scheme and the downlink data is modulated using a second different modulation scheme. 
     
     
         8 . The method of  claim 1 , wherein the uplink data or downlink data further includes feedback information or error information indicating whether data transmitted in one or more previous frames is received successfully or with a satisfactory quality. 
     
     
         9 . A terminal comprising:
 an uplink transmitter; and   a downlink receiver,   wherein the uplink transmitter is configured to:
 determine that the downlink receiver is not receiving downlink data from a movable object based on a state of the downlink receiver; 
 generate first synchronization information in response to determining that the downlink receiver is not receiving the downlink data from the movable object, the first synchronization information being provided to the downlink receiver to prevent operation of the downlink receiver; 
 transmit uplink data to the movable object; and 
 generate second synchronization information in response to completion of uplink data transmission, the second synchronization information being provided to the downlink receiver to allow operation of the downlink receiver. 
   
     
     
         10 . The terminal of  claim 9 , wherein the uplink data includes control data to control the movable object and third synchronization information, wherein the third synchronization information is configured to synchronize data transmission with the movable object. 
     
     
         11 . The terminal of  claim 9 , wherein the downlink receiver is configured to:
 measure one or more quality characteristics of each of a plurality of working frequency channels to determine measured quality characteristics; and   select a working frequency channel from the plurality of working frequency channels based on the measured quality characteristics.   
     
     
         12 . The terminal of  claim 11 , wherein the downlink receiver is further configured to:
 receive the downlink data from the movable object using the working frequency channel in response to receiving the second synchronization information from the uplink transmitter.   
     
     
         13 . The terminal of  claim 11 , wherein the one or more quality characteristics include at least one of noise, interference, signal-to-noise ratio (SNR), bit error rate, or fading rate. 
     
     
         14 . The terminal of  claim 9 , wherein the uplink data or downlink data further includes feedback information or error information indicating whether data transmitted in one or more previous frames is received successfully or with a satisfactory quality. 
     
     
         15 . A computer-readable storage medium storing a computer program that, when executed by one or more processors, causes the one or more processors to:
 determine that a downlink receiver is not receiving downlink data from a movable object based on a state of the downlink receiver;   generate first synchronization information in response to determining that the downlink receiver is not receiving the downlink data from the movable object, the first synchronization information being provided to the downlink receiver to prevent operation of the downlink receiver;   transmit uplink data to the movable object; and   generate second synchronization information in response to completion of uplink data transmission, the second synchronization information being provided to the downlink receiver to allow operation of the downlink receiver.   
     
     
         16 . The computer-readable storage medium of  claim 15 , wherein the uplink data includes control data to control the movable object and third synchronization information, wherein the third synchronization information is configured to synchronize data transmission with the movable object. 
     
     
         17 . The computer-readable storage medium of  claim 15 , wherein the computer program, when executed by the one or more processors, further causes the one or more processors to:
 measure one or more quality characteristics of each of a plurality of working frequency channels to determine measured quality characteristics; and   select a working frequency channel from the plurality of working frequency channels based on the measured quality characteristics.   
     
     
         18 . The computer-readable storage medium of  claim 17 , wherein the computer program, when executed by the one or more processors, further causes the one or more processors to:
 receive the downlink data from the movable object using the working frequency channel in response to the generated second synchronization information.   
     
     
         19 . The computer-readable storage medium of  claim 17 , wherein the one or more quality characteristics include at least one of noise, interference, signal-to-noise ratio (SNR), bit error rate, or fading rate. 
     
     
         20 . The computer-readable storage medium of  claim 15 , wherein the uplink data or downlink data further includes feedback information or error information indicating whether data transmitted in one or more previous frames is received successfully or with a satisfactory quality.