Receiver Controlled Isochronous Transmission

Abstract

A Bluetooth radio transceiver, for receiving isochronous data, comprising: receiving means for receiving data; determining means for determining whether the received data has been correctly or incorrectly received; validation means for determining whether the received data is current; and transmission means, for transmitting, in response to received data, a positive acknowledgement of reception when the received data has been correctly received, a negative acknowledgement when the received data has been incorrectly received and the received data is current and a positive acknowledgement when the received data has been incorrectly received and the received data is not current is described. The determination of whether data is current occurs at the receiver as opposed to the transmitter.

1 . An apparatus comprising: 
 a receiving component configured to receive data;    a determining component configured to determine whether the received data has been correctly or incorrectly received;    a validation component configured to determine whether the received data satisfies a condition;    a transmission component, configured to transmit, in response to the received data, 
 a positive acknowledgement of reception when the received data has been correctly received,  
 a negative acknowledgement when the received data has been incorrectly received and the received data satisfies the condition, and  
 a positive acknowledgement when the received data has been incorrectly received and the received data does not satisfy the condition.  
   
   
   
       2 . The apparatus as claimed in  claim 1 , further comprising a component configured to flag the incorrectly received data for which a positive acknowledgement has been sent.  
   
   
       3 . The apparatus as claimed in  claim 2 , further comprising a buffer configured to buffer the received data.  
   
   
       4 . The apparatus as claimed in  claim 3 , wherein the validation component is coupled to the buffer wherein the determination of whether the received data satisfies the condition is dependent upon content of the buffer.  
   
   
       5 . The apparatus as claimed in  claim 1 , wherein the received data is isochronous data.  
   
   
       6 . The apparatus as claimed in  claim 1 , wherein the receiving component is configured to receive data as data packets having a payload which includes isochronous data.  
   
   
       7 . The apparatus as claimed in  claim 6 , wherein the validation component determines whether the received data is isochronous data, in addition, to whether the isochronous data satisfies the condition.  
   
   
       8 . The apparatus as claimed in  claim 7 , wherein the received data includes an indication of whether the payload includes isochronous data, wherein the validation component is further configured to determine whether the received data is isochronous data in dependence upon said indication.  
   
   
       9 . The apparatus as claimed in  claim 1 , wherein said validation component comprises a timer configured to determine whether the received data is current.  
   
   
       10 . The apparatus as claimed in  claim 1 , wherein said data is received in a payload of a packet having a header, and said determining component is configured to determine whether the packet has been correctly or incorrectly received by testing integrity of the header.  
   
   
       11 . The apparatus as claimed in  claim 1 , wherein said data is received in a payload portion of a packet, and said determining component is further configured to determine whether the packet has been correctly or incorrectly received by testing integrity of the payload.  
   
   
       12 . The apparatus as claimed in  claim 11 , wherein said payload portion includes a Cyclic Redundancy Check.  
   
   
       13 . The apparatus as claimed in  claim 1 , further comprising an error correction component configured to correct errors in incorrectly received data.  
   
   
       14 . The apparatus as claimed in  claim 1 , further comprising: 
 a component configured to determine an improved version of first data, the component configured to determine an improved version having received consecutively a plurality of incorrect versions of said first data for which a negative acknowledgement has been sent; and    a buffer for retaining the improved version after the transmission of a positive acknowledgement.    
   
   
       15 . The apparatus as claimed in  claim 1 , wherein the condition is that the data is current.  
   
   
       16 . The apparatus as claimed in  claim 1 , wherein the condition is that the data is both isochronous and current.  
   
   
       17 . The apparatus as claimed in  claim 1 , wherein the condition is dependent upon an amount of data in a memory buffer.  
   
   
       18 . A system comprising: 
 a transmitter, the transmitter configured to transmit packets of data having payloads including isochronous data, the transmitter comprising: 
 a first transmission component configured to transmit a packet of data to a receiver; and  
 a first reception component configured to receive from the receiver, in response to said transmission of the data packet, a positive acknowledgement or a negative acknowledgement, wherein the transmitter is arranged to retransmit a data packet comprising isochronous data, unless a positive acknowledgement is received; and  
   the receiver comprising: 
 a second receiving component configured to receive data transmitted by the transmitter;  
 a determining component configured to determine whether the received data has been correctly or incorrectly received;  
 a validation component configured to determine whether the received data is current; and  
 a second transmission component configured to transmit in response to received data, 
 a positive acknowledgement of reception when the received data has been correctly received,  
 a negative acknowledgement when the received data has been incorrectly received and the received data is current, and  
 a positive acknowledgement when the received data has been incorrectly received and the received data is not current.  
 
   
   
   
       19 . A method comprising: 
 receiving data;    determining whether the received data has been correctly or incorrectly received;    determining whether the received data satisfies a condition;    transmitting a positive acknowledgement when the received data has been correctly received, a negative acknowledgement when the received data has been incorrectly received, and a positive acknowledgement when the received data has been incorrectly received and the received data does not satisfy the condition.    
   
   
       20 . The method as claimed in  claim 19 , further comprising flagging the incorrectly received data for which a positive acknowledgement has been sent.  
   
   
       21 . The method as claimed in  claim 20 , further comprising using the flagged incorrectly received data to correct received data.  
   
   
       22 . The method as claimed in  claim 19 , further comprising buffering received data in a memory buffer, wherein the condition is dependent upon content of the memory buffer.  
   
   
       23 . The method as claimed in  claim 19 , wherein the condition is that the data is current.  
   
   
       24 . The method as claimed in  claim 19 , wherein the condition is that the data is both isochronous and current.  
   
   
       25 . The method as claimed in  claim 19 , wherein a positive acknowledgement is transmitted unless the received isochronous data is both incorrectly received and satisfies the condition.