Patent Publication Number: US-2004053631-A1

Title: Electronic systems

Description:
[0001] The present invention relates to improvements in or relating to electronic systems.  
       [0002] Electronic systems are becoming increasingly complex whether at board level or chip scale. At the same time, such systems are required to handle greater volumes of data at higher rates. In order to implement these systems successfully, the processing is commonly broken down into manageable and testable sub-functions. These sub-functions must intercommunicate to pass the data and control signals to complete the system. However, the difficulty of providing the necessary interconnections to allow the intercommunication and providing sufficient flexibility causes bottlenecks in the electronic systems.  
       [0003] It is therefore an object of the present invention to provide an improved electronic system which overcomes the problems mentioned above.  
       [0004] In accordance with one aspect of the present invention, there is provided a sub-function node for an electronics system having a radio link.  
       [0005] The node further includes an antenna and transceiver means for transmitting and receiving radio signals. The transceiver means may comprise a receiver and a transmitter. Communication controller means is provided for controlling the antenna and transceiver means.  
       [0006] The node further includes processing means for processing received data.  
       [0007] In accordance with another aspect of the present invention, there is provided an array comprising a plurality of sub-function nodes as described above.  
       [0008] The array includes a secondary bus and a system communication controller for distributing timing and synchronisation signals over the secondary bus to the sub-function nodes. The system communication controller also supplies enabling signals for establishing radio links between sub-function nodes.  
       [0009] In accordance with a further aspect of the present invention, there is provided an electronics system including at least one array as described above.  
       [0010] In accordance with yet another aspect of the present invention, there is provided a method of operating an electronics system, as described above, comprising the steps of:—a) supplying control signals via the secondary bus; and b) transmitting data signals via the radio links.  
       [0011] Step b) may comprise using a multiple access technique. The multiple access technique may comprise frequency division multiple access, code division multiple access, or time division multiple access. A combination of these techniques could also be used.  
       [0012] Step a) comprises supplying timing and synchronisation signals for the sub-function nodes. Step a) further comprises supplying access signals to the sub-function nodes for the radio links. 
     
    
    
     [0013] For a better understanding of the present invention, reference will now be made, by way of example only, to the accompanying drawings in which:— 
     [0014]FIG. 1 illustrates a processing array in accordance with the present invention; and  
     [0015]FIG. 2 illustrates a sub-function node used in the processing array of FIG. 1.  
    
    
     [0016] The present invention provides a high bandwidth, flexible method for providing intercommunication between sub-function nodes in a complex electronic system. The invention uses the transmission and reception of radio borne multiple access signals between the sub-function nodes for the transmission of data between the sub-function nodes, each sub-function node being equipped with a transceiver. A secondary, lower speed conventional backplane is used to distribute timing and synchronisation signals along with multiple access parameters.  
     [0017]FIG. 1 shows an array  10  in accordance with the present invention. The array  10  comprises forty-two sub-function nodes  20  (only one labelled for clarity) arranged in a six by seven array. It will be appreciated that, although a particular array is shown in FIG. 1, any number of sub-function nodes  20  can be utilised in any suitable configuration. As shown in FIG. 1, seven sub-function nodes  20  are connected to an arm  30 A,  30 B,  30 C,  30 D,  30 E,  30 F of a secondary bus  30  via respective links  32 . A system communication controller  40  is connected to the secondary bus  30  for controlling the secondary bus  30  and its connecting arms  30 A,  30 B,  30 C,  30 D,  30 E,  30 F and hence each sub-function node  20 . The secondary bus  30  and its connecting arms  30 A,  30 B,  30 C,  30 D,  30 E,  30 F comprise a conventional backplane. The system communication controller  40  is responsible for distributing time and synchronisation signals for the sub-function nodes  20  along the secondary bus  30 ,  30 A,  30 B,  30 C,  30 D,  30 E,  30 F.  
     [0018] In accordance with the present invention, the system communication controller  40  also sets the connectivity for radio access between the sub-function nodes  20  by the distribution of multiple access ‘tokens’. Various multiple access techniques can be used, for example, frequency division multiple access (FDMA), code division multiple access (CDMA) or time division multiple access (TDMA) techniques. Each link between sub-function nodes  20  is characterised by a ‘token’. For example, in a TDMA scheme, the ‘token’ would allocated a particular time slot number to an inter-node link. For other multiple access schemes, a ‘token’ might represent a spreading code or carrier frequency etc.  
     [0019] A sub-function node  20  is shown in more detail in FIG. 2. Each sub-function node  20  is equipped with an antenna  50 , a receiver  52 , a transmitter  54  and a node communications controller  56 . Each sub-function node  20  also includes a sub-function node processor  58  which executes the sub-function associated with that particular sub-function node  20 . As shown in FIG. 2, the antenna  50  is connected to both the receiver  52  and the transmitter  54  by connections  60  and  62  respectively. The receiver  52  and transmitter  54  are connected to the sub-function node processor  58  via connections  64  and  66  respectively. Received signals are transferred from the receiver  52  to the processor  58  for processing via connection  64 . Signals to be transmitted from the sub-function node  20  are generated in the processor  58  and are transferred to the transmitter  54  via connection  66 .  
     [0020] The receiver  52  and transmitter  54  are connected to the node communication controller  58  via control lines  68  and  70  respectively. The node communication controller  58  is also connected to the sub-function node processor  58  via connection  72 .  
     [0021] As described above, the node communication controller  56  is connected to the secondary bus  30  via link  32 . Control signals are transmitted to the receiver  52  and transmitter  54  via the control lines  68 ,  70  and to the sub-function node processor  58  via connection  72  in accordance with the signals received from the secondary bus  30  via the link  32  so that the antenna  50  is switched between a receiving mode and a transmitting mode.  
     [0022] The carrier frequencies of the radio signal used in this invention are not fundamental to its operation. However, in order to support the high bandwidths (one of the advantages of the present invention), they would need to be quite high, for example, in excess of tens of GHz.  
     [0023] The system communication controller  40  shown in FIG. 1 is responsible for setting up and tearing down links between sub-processing nodes  20 . These links may be uni- or bi-directional, point-to-point, point-to-multi-point or a combination thereof.  
     [0024] The links may be set up according to a predetermined schedule or may be set up dynamically as they are required by the processing architecture. If a predetermined schedule is used, the schedule is stored in the system communication controller  40  and the ‘tokens’ are distributed to the sub-function nodes  20 . The schedule could be fixed and loaded once shortly after powering up the electronic system of which the array  10  forms a part. Alternatively, the schedule may be variable with time and the links are modified in accordance with a predetermined timetable.  
     [0025] If the allocation of links is dynamic, the connectivity of the system is event data driven. A sub-function node  20  determines in its sub-function node processor  58 , according to its current data processing state, if a link to another node  20  is necessary. If such a link is necessary, a request is made by the processor  58  via connection  72  to the node communication controller  56  which, in turn, passes the request to the system communication controller  40  via link  32  and over the secondary bus  30 . The system communication controller  40  then sets up the link by distributing a transmission ‘token’ to the node requiring to transmit and a reception ‘token’ to the appropriate sub-function node which needs to receive. Once the reception ‘token’ is received at the sub-function node  20  which is to receive over the secondary bus  30  and link  32 , the node communications controller  56  configures the receiver  52  according to the received ‘token’. Similarly, for the sub-function node which is to transmit, once the transmit ‘token’ is received over the secondary bus and link  32 , the communications controller  56  configures the transmitter  54  according to the transmit ‘token’.  
     [0026] The present invention has application in integrated circuits, racks of printed circuit boards or modules. As there is no specific size requirements, the invention can also be applied to larger scale systems.