GB2404119A

GB2404119A - Operating a radio module in accordance with first and second wireless communication protocols during first and second time periods respectively

Info

Publication number: GB2404119A
Application number: GB0423209A
Authority: GB
Inventors: James P Kardach; Jeffrey Schiffer
Original assignee: Intel Corp
Current assignee: Intel Corp
Priority date: 2001-03-29
Filing date: 2002-03-01
Publication date: 2005-01-19
Anticipated expiration: 2022-03-01
Also published as: GB0423210D0; GB0423209D0; GB2404120B; GB2404120A; GB2404119B

Abstract

A method of operating a radio module partitioned to meet government regulations with protocol flexibility operates the module in accordance with a first wireless communication protocol during a first period of time, the radio module meeting with LMA approval by the FCC or similar type approval relevant to the U.K. independent of the computer system. The method further enables the computer system to operate the radio module in accordance with a second wireless communication protocol during a second period of time.

Description

240411 9 t

METHOD FOR PROVIDING A RADIO MODULE

FOR A COMPILER SYSTEM

The preset invention relates bo computer systems and more particularly to a method of opening a radio module partitioned to meet government Legations with protocol flexib - .

BACKGROUND

Mobile computer systems, from small handheld electronic devices to appleationpeciFic electronic comporents, such as set-top boxes, to mediumshed notebook and laptop systems, are becoming increasingly pervasive in our society. Unlike their symmeinc muRiprocessg courrparts, such as sender, workstation, and high-end desktop systems, mobile computer systems Epically indude a single, primary, host processor coupled to venous peripheral devices.

Computer system designers continually strive to provide more features to users without significantly incising Me cost of fife system. Unfortunately, each additional [eabure typicaJiy corresponds fo additional components added to the computer system, resulting in increased so and expense.

According to a first aspect ofthis invention there is probed a method as claimed in claim 1 herein - According to a second aspect of this invention there is lúrov:ed a mobile, pcessor confer Enemas claimed include 8 harem Accog to a third aspect of invendone is provided a mRebine- accessle media as claimed in claim 9 herem.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention is illustrated by way of example and not limitation in Me accompanying figures in which like references indicate similar elements and in which: Figures la-d are systems useful in understanding the present invention; Figure 2a is a processor fomned in accordance With an embodiment of the present invention; Figure 2b is a flow chart showing a method of the present invention; and Figure 3 is a computer system which may be used with the present mventon.

DETAILED DESCRIPTION

In the preset mventton, a scalable interface (refened to herein as a "hannonized tnbefface-) mom a host computer system a wireless radio module is pried. The module meets me legal requirements for an nfional radiator but may not be specific any given wireless communication prolocot On He offer elde of me harmonized interface resides a generic protocol engine that can manipulate Me we module to meet a given voteless common protocol. Siding above me protocol engine resides me normal opening system {OS) darer static Off then connect to He different nshYorldag and Cal drivers riffle host computer so Wan this type of partitioning, a So module may be designed to operate in accordance won multiple wireless communcabon protocols. The hamwnized interface may connect As radio module to a host computer system mat then perform file high level baseband processeytor the module. By dyrmicaly changing me source code hi the host system, dfflerentwless communication protocols may be emulated.

For example a me - : may be creed that operates m acoordce He Bluelooth* (as described in, e.g., "Specification of the Bfuetoo System," v1.0b, December 1", 1999), HomeRF* {;;hared Winless Access Protocol (SWAP) (as described in, e.g., "Shari voteless Access Protocol (SWAP) Specification v.1.0, January 5, 1999), and IEEE 8011 (as descried in, e.g. , IEEE Std 802.111999 Edition) protocols. The protocol may be changed dynamically depending on the environment of the user (em. on the road, in the once, or at home). In addition to these short-range wireless communication protocols, long range wireless communication protocols may also be emulated, such as a Third Generation (3G) cellular communication protocol, given the appropriate module attached to the harmonized interface. (trademarks and brands are the property of their respective owners.) {3y partitioning the baseband correctly, such a design may also allow the host processor of the host computer system to perform some of the higher level baseband processing. Using the harmonized interface, a host processor of a computer system may perform baseband processing functions natively, thereby reducing the cost of the system by reducing the need for separate, specialized processing hardware to support the radio module. To perform these functions, the host processor may include enhancements over conventional processors that enable the host processor to process reaFtirne events, such as those associated with wireless communication protocols.

A more detailed description ofthe present invention, including various configurations and implementations, is provided below.

THE WIRELESS MODULE

Although much of the following discussion focuses on Bluetooth technology, including Me t31uetooth baseband, it is to be appreciated that the concepts discussed herein may be more broadly applied to nearly any Wireless communication protocol and its respective baseband.

Current partitioning of a wireless Bluetooth module follows the silicon technology used for the implementation. The radio frequency (RF) analog portion of a Bluetooth module is typically manufactured using a Bl-CMOS process, and resides in one device (e.g. the transceiver). The remaining micro-controller section is typically rnanufacred using a CMOS process, and resides in a separate device, referred to herein as the short range wireless baseband controller.

The [31uetooth system is based on radio technology. Consequently, compliance with a number of count-specific regulator requirements may be important for the success of the E31uetooth protocol. These requirements are normally tracked by a government agency, including, for example, the Federal Communications Commission (FCC) in the United States and the Ministry of Posts and Telecommunications (MPT) in Japan. Their requirements dictate how a compliant radio is to behave within their respective counky. After a product to be sold has been assembled, it is sent to a government agency-approved testing facility to be tested and certified. After this testing is complete (which may take two months or more) and the product is certified, the product may then be sold in that country's markets.

To speed up product introduction of such devices, a process called Declaration of Compliance (DoC) has been created. This process allows a company to pre-certifir a device based on the fact that it is assembled with pre tested (and prcertified) components. Building a device using a pre-cer0tied component allows a company to self-certify their final product through the DoC process. In the United States, to achieve precertification of a wireless module, the module may be expected to meet the requirements of Limited Modular Approval (LMA3 as described in the FCC publication entitled Part 15 Unlicensed Modular Transmitter Approval" published June 26, 2000.

In the present invention, a radio module is provided that meets the FCC's LMA requirements such that an OEM can use the DoC process to self-certify their end-user products incorporating the module. This removes from the product development cycle the FCC radio certification process normally associated with integrating an intentional RF radiator into a product. Current DoC requirements for LMA extend up through the equivalent of the Bluetooth Link Management Protocol, and because of the present manufactunng-based partitioning described above, a radio module, to obtain LMA, may contain the entire Bluetooth baseband.

For example, consider the computer system of Figure 1a comprising processor 30S, memos 31 S. and input-output (I-O) device 320 coupled to bus - control logic 310 (which is typically the system chipset). Short range wireless baseband controller 330 contains the logic associated with the full baseband, e.g. the Bluetooth baseband, used to operate transceiver 335. In other words, baseband controller 330 contains all the logic used to support the full baseband of a wireless communication protocol. In addition, controller 330 contains bus interface logic used to communicate Bath bus control logic 310 of the chipset and wffl transceiver 335.

Based on this partitioning, a module that meets the requirements for LMA would contain both transceiver 335 and short range wireless baseband controller 330 of Figure 1a. An upgrade or other modification to the baseband, contained within controller 330, may therefore require re-certification of such a module. In addition, such a module leaves little if any of the baseband processing to be implemented by the host computer system, thereby increasing system costs.

Altemabvely, integration of controller 330 into the host computer system would cause what is leftover, transceiver 33S, to not be subject to the DoC process because it would not meet LMA requirements.

In an embodunent of the present invention, short range wireless baseband controller 330 of Figure 1a is split such mat some of the baseband may be integrated into one or more devices of the host computer system. The portion of the baseband that is not integrated into the host system corresponds to the I ink Management Protocol, thereby making this portion available, along with the transceiver, to satisfy MA of Me 13OC process.

For example, consider the computer system of Figure 1b comprising processor 305, memory 315, and l-O device 320. These elements are coupled to bus control logic 311. Bus control logic 311 includes an integrated high-level baseband controller 312 associated With the highlevel portion of the Bluetooth (or other wireless communication protocol) baseband, previously contained within controller 330 of Figure 1 a. The remaining lout level portion of me baseband, previously contained within controller 330, is now contained within low-level baseband controller 331. This controller, along with transceiver 336, now constitutes new radio module 340 used in the present invention, and this module is coupled to bus control logic 311, containing high-level baseband controller 312, via a hannonized interface.

Radio module 340 of Figure 1b may be prcertified by the FCC (or analogous agencies of foreign countries) using the LMA and DoC processes, and sold as an independent, add-on component to computer system manufacturers for connecting to their systems. In the present invention, radio module 340 includes extemalJy accessible l-O ports coupled to l O buffers within Me module. These interconnects may be designed to be coupled to one or more components of the host computer system to enable communication between the module and the host computer system.

By designing radio module 340 of Figure 1b generically, the module may support multiple protocols, and each may share some segment of the baseband portion contained within radio module 340. Protocol-specific baseband processing is performed in the high-level portion of the baseband, which is coordinated by high level baseband controller 312 integrated into bus control logic 311. Baseband protocol selection and operation may be controlled, at least in part, by one or more software programs that may or may not involve direct user interaction. These programs may reside, at least in part, on any machine- accessible medium such as a magnetic disk (e.g. a hard drive or floppy disk), an optical disk (e.g. a CD or DVD), a semiconductor device (e.g. Flash, EPROM, or RAM), or carder wave, all of which are collectively represented by l-O devices 320 of Figures 1a-c.

In accordance with one embodiment of the present invention, the single radio module may nun different protocols depending on the environment of the user. For example, while traveling a user may use the module to execute Elluetooth protocols. In the office, the user may use the module to execute IEEE 802.11 protocols, and at home the user may use the module to execute SWAPlHome-RF protocols. In accordance with another embodiment of the present invention, the module supports other wireless communication protocols that also operate in the 2.4GHz band. Altematively, the module may be modified to support wireless communication protocols that operate in other radio bands.

In accordance with one embodiment of the present invention, execution of the high-level baseband protocols (baseband processing) is done by (or aided by) host processor 305 of Figure 1 b, which may be modified to support real-time event processing as described below. AItematively, all or a portion of the high level baseband processing may be performed by control logic embedded within bus control logic 311. Alternatively, execution of the high-level baseband protocols is done by (or aided by) a peripheral controller ofthe host system, as described below in conjunction with Figure 1c.

The computer system of Figure 1c comprises processor 305, memory 315, and l-O device 320 coupled Gina bus control logic 310. In addition, embedded controller 325 is coupled to bus control logic 310. Embedded controller 325 may be, for example, a keyboard controller or long-range or reless controller.

Embedded controller 325 includes highlevel baseband controller 326 interfacing to radio module 340 via the harmonized interface. The arrangement depicted in - Figure 1c may be found advantageous over the arrangement of Figure lb in that the arrangement of Figure 1c provides for opamion ofthe radio module even when the processor may be in a power-down (low power) state. The arrangement of Figure lb may be found advantageous in that baseband processing by the host processor reduces system cost because it reduces the need for a separate controller.

In addition to Me features of the radio module described above, the module may include features that enable the module to recede L5/IA from the FCC as an intentional radiator, and its equivalent from other governments. For example, the radio module may additionally include its own reference oscillator, antenna, RF shielding, buffered data inputs, and power supply regulator.

The interconnect between the radio module and the host system components may indude a flexible cable, such as a ribbon cable, that may span six inches or more.

The length of such a cable may be selected to span the distance from the lid of a notebook or other mobile computer system, through the hinge of the host system to the motherboard for coupling to other components. The radio module, including its antenna, may be advantageously affixed to the lid.

For example, Figure 1d shows notebook computer system 400 comprising base 410 coupled to hinged lid 405. The motherboard ofthe computer system, contusing, for exile, the processor, chipset (bus control logic), mom memory, and high-level baseband controller, is included in base 410 of computer system 400. Lid 405 ofthe computer system includes a display screem Alternatively, a lid of an alternate computer system, such as a tablet or handheld computer system, may be any protective cover with or without a display screen Of other inputloutput functionality.

One advantage to placing radio module 340 in lid 405 of Figure 1d is that, during nonnal operation, lid 405 typically exists as the highest point in the computer system, thereby aiding in wireless communication. As shown, radio module 340 may be affixed within lid 405 at location 415, at or near the top of lid 405, with flexible cable 420 extending down through lid 405 and through the hinged coupling between lid 405 and base 410. The end of cable 420, opposite radio module 340, may then be coupled to components within base 410, such as the high-level baseband controller which may be integrated into a chipset or micro-controller of the motherboard within base 410. Note that radio module 340 and cable 420 are shown removed from lid 405 in Figure 1d for clanty. In the arrangement described above, the radio module and cable are integrated within the lid or otherwise affixed to the lid.

REAL-TIMP EVENT PROCESSING

Note that as used herein, the term "real-time" is not intended to imply that a host system responds instantaneously to a signal generated by an external; device. Rather, the term real-time. is intended to imply sufficient detemminism and sufficiently reliable latency on the part of the host system to, for example, reliably enable the establishment and maintenance of a wireless communication link with an external device. For one embodiment of the present invention, this wireless communication link may be in accordance With a Bluetooth or other wireless communication protocol. The external device may be an electronic device having an independent processor that not under direct control of the host processor of the host system. 3 A primary host processor may be modified to process real-time events such as those associated with establishing a wireless communication link with an external device in accordance with a Bluetooth or other wireless communication protocol. One manner in which a conventional host processor may be modified to process these real-time events is to include a timer and a high priority event (interrupt) circuit in the host processor. This may enable a real-time kernel to run underneath an existing operating system that does not have real-time attributes.

An example of an operating system that does not have real-time attributes includes the Windows. operating systems such as Windows NT, Windows 2000, Endows 98, and VVindows ME (Millennium Edition). (*Trademarks and Brands are the property of their respective owners). It

This kernel may set the timer to generate the high priordy event at regular intervals. Upon activaticn, a real-time event circuit may transfer control to a real- time event handler (kernel sofvare) which may perform a real-ffme task. This handler may be used to process a wireless baseband protocol that has strict timing requirements. Additionally, this method may encompass the use of an event pin which may also generate this high priority event. The event pin may be coupled to the processor itself or to an external device coupled to the processor, such as a chipset. For an alternate embodiment of the present invention, the high priority event may be generated using a status bit stored within the processor or in an external device.

One feature of this high priority event is that it may provide more reliable latencies over conventional interrupts, reducing the risk of a high priority event latency being upset by other tasks being performed by the processor. Hence, in accordance with one embodiment of the present invention, this high priority event is one of the highest priority interrupts in the processor, although other interrupts, such as may be used for memory error handling, may be of higher priority.

Hardware and software elements used in the present invention are shown in Figures 2a and 2b, respectively. Host processor includes an interval timer 105 that may be set by a software routine. The timer triggers real- ffme event circuit 110 to implement the method of Figure 2b.

Alternatively, interval timer 105 may trigger real-time event circuit 110 to read a register to determine if a real-time event has been received. For another embodiment, host processor 100 includes an externally accessible event pin 115 that may be used by external devices w thin the host computer system to trigger real-time event circuit 110 to implement the method of Figure 2b. /2

In the arrangement of Figure 2b, the processor is executing a process at step 150 when a real-time event interrupt (REI) occurs at step 155. This REI may be caused by, for example, event timer 105 expiring its set time interval or the activation of event pin 115 of host processor 100 of Figure 2a. In response to the REI, real-time event circuit 110 causes host processor 100 to halt the process being executed at step 150 and save the processor state at step 160. The processor state may be saved to a reserved memory space flit step 165 of Figure 2b, host processor 100 calls and executes a REI handler. In accordance with one embodiment of the present invention, this REI handler includes instructions that, when executed by the host processor, cause the host processor to read one or more registers mat store information related to the real-Une event. For example, Me host processor may read one or more registers that store information indicating the presence or absence of a wirelessly transmiffed identification signal from an external device requesting wireless communication.

If it is determined that an external device is present and requests -I communication, the host processor may establish communication (or may establish a schedule for future communication) with the external deuce at this time. Altematively, the host processor may, during this time, perform baseband processing functions in accordance with a wireless communication protocol as described above.

After a REI retum instncffon is received at step 170 of Figure 2b, the processor state stored in the reserved memory space may be restored to me host processor, and the previous process (exited from step 150) may continue. Note /3 that the above-described hardware and software may be implemented either with or without OS support.

In an alternate embodiment of the present invention, real time event processing may be implemented via a secondary non-symmetric processor (NSP) integrated into the primary host processor. For this embodiment, the NSP may execute an OS that supports real-time processing separate from the primary OS executed by Me primary host processor, which may not support n3at- time functionality. In this embodiment, the NSP may then perform the baseband processing functions in accordance With a wireless communication protocol, as described above, while the primary processor performs the regular work of the host processor for the remainder of the computer system.

Figure 3 includes a host processor 200 used in the present invention in which NSP core 210 is integrated with the primary host processor core 205. In this arrangement, the NSP core is integrated on the same semiconductor substrate as the primary host processor core to form a single processor. To reduce cost, primary host processor core 205 and NSP core 210 share L2 caclie 21 S. and both processor cores may communicate via bus unit 215 to a shared memory subsystem NO of the host computer system. Both cores may additionally share, other system resources.

Preferably, the NSP core and primary host processor core share an instruction set architecture (ISA). For an alternate arrangement ofthe present invention, the NSP and primary host processor cores do not share an ISA.

Claims

CLAIMS: 1. A method comprising: enabling a computer system to operate a

radio module in accordance with a first wireless communication protocol during a first period of time, the radio module meeting Limited Modular Approval by the Federal Communications Commission or similar type approval relevant to the U.K. independent of the computer system; and enabling the computer system to operate the radio module in accordance with a second wireless communication protocol during a second period of time.
2. The method of claim 1, wherein enabling the computer system to operate the radio module includes enabling signals to be transmitted between the computer system and the radio module via a flexible cable coupled to a motherboard of the computer system at a first end and coupled to the radio module affixed to a lid of the computer system at a second end.
3. The method of claim 1, wherein enabling a computer system to operate a radio module in accordance with a first wireless communication protocol includes enabling a first portion of baseband processing associated with the first wireless communication protocol to be performed by the computer system and enabling a second portion of baseband processing associated with the first wireless communication protocol to be performed by the radio module.
4. The method of claim 3, wherein the first wireless communication protocol is a Bluetooth protocol, and the second portion of baseband processing is in accordance with the Bluetooth link management protocol.
5. The method of claim 4, wherein the second wireless communication protocol is an IEEE 802, 11 or SWAP protocol. /d l
6. The method of claim 3, wherein enabling the first portion of baseband processing associated with the first wireless communication protocol to be performed by the computer system includes equipping the computer system with a chipset having an integrated baseband controller.
7. The method of any preceding claim, wherein enabling a computer system to operate a radio module in accordance with a second wireless communication protocol includes equipping the computer system with a keyboard controller having an integrated baseband controller to perform a first portion of baseband processing associated with the second wireless communication protocol, and enabling a second portion of baseband processing associated with the second wireless communication protocol to be performed by the radio module.
8. A mobile, uniprocessor computer system programmed to implement the method of any of claims 1 - 7.
9. A machine-accessible medium including machine-accessible instructions that, when executed by a computer system, cause the computer system to perform the method of any of claims 1 - 7. /G