Showing papers on "Paging published in 1993"

Lightweight recoverable virtual memory

Abstract: Recoverable virtual memory refers to regions of a virtual address space on which transactional guarantees are offered. This paper describes RVM, an efficient, portable, and easily used implementation of recoverable virtual memory for Unix environments. A unique characteristic of RVM is that it allows independent control over the transactional properties of atomicity, permanence, and serializability. This leads to considerable flexibility in the use of RVM, potentially enlarging the range of applications than can benefit from transactions. It also simplifies the layering of functionality such as nesting and distribution. The paper shows that RVM performs well over its intended range of usage even though it does not benefit from specialized operating system support. It also demonstrates the importance of intra- and intertransaction optimizations.

Apparatus and method for TLB purge reduction in a multi-level machine system

Abstract: A system for reducing purging of a translation lookaside buffer (TLB) to reduce operating system overhead in a system running multiple levels of virtual machines. A system typically must purge TLB entries whenever an underlying page table entry is invalidated due to paging activity on the host machine, or an underlying guest machine. A system for reducing the number of cases in which guest translations are based on host page table entries is provided. Additional logic is supplied to analyze each invalidate page table entry (IPTE) instruction to minimize the extent of purging required as a result of that instruction. When the region relocate facility is in operation, or when no pageable TLB's have been constructed, only the entry corresponding to the page table entry to be invalidated need be purged. This limited purging reduces the overhead by reducing the time spent in purging and the time required in address translation to rebuild the TLB. This time saving results in increased performance in systems with multi-level guests.

Cellular communications system utilizing paging areas

Abstract: A system for paging mobile stations within a cellular telecommunication system wherein paging areas, which are composed of a plurality of location areas, are created to provide a means for locating a mobile station when the mobile station has not responded to a location area page and without requiring a service area page. The system sends a page request to the location area where the desired mobile station last registered. If a response is not received, the system sends a page request to the paging area which includes a plurality of location areas where the mobile station is likely to be found. If a page response is still not received from the desired mobile station, then a page request will be sent to all of the location areas within the service area.

A person paging method

Abstract: A person paging method in which a first user (A) wishes to page and transmit a message to a second user (B) with the aid of a paging service. The first user (A) requests paging of the second user (B) at a paging central (1) which offers an alerting service and a message service which supplements the alert with the message. The paging central (1) alerts the second user (B) by means of the alerting service. The invention is characterized in that the paging service is not associated with any particular telecommunication network, but can be performed in at least one telecommunication network (e.g. in N1 and N5) chosen from among at least two possible telecommunication networks (N1-N5). The message service is also made independent of the alerting service, in that the message service is not activated until a request to do so is received from the second user. The alerting service utilizes the aforesaid first telecommunication network (N1-N5) while the message service utilizes at least one telecommunication network (N1-N5) which is selectively different from the first-mentioned network (N1 and N5). The message is not transmitted until the aforementioned request is received.

Location updating in a cellular radio network

Abstract: The invention relates to a cellular radio network and a mobile station. In addition to location updating of a mobile station with the accuracy of one location area (LA), a so-called temporary subscriber-specific paging area (TPA') is determined. The mobile station initiates the determining of the temporary paging area in the subscriber database of the cellular radio network after being located in a cell (X) for a sufficiently long period. The temporary paging area (TPA') is smaller than the location area (LA) (e.g. one cell), and thus the paging of a mobile station can be focused on a small area, i.e. said temporary paging area. It is thus unnecessary to page over the entire location area, and paging time can be reduced and capacity of the cellular radio network spared.

Portable real time cellular telephone and pager network system monitor

Abstract: A portable real-time monitoring system for field testing and troubleshooting a cellular telephone network, paging network, or mobile radio system employs a user friendly interface between a user and a scanning radio receiver which displays, monitors and stores parameters related to real-time performance. A portable all-band radio receiver capable of receiving cellular and paging frequencies is connected to a computer, such as, for example, a lap-top computer suitable for mobile operation at remote sites, personal computer (PC) or workstation. An interface circuit is installed within the radio receiver which taps available signals within the receiver as well as allows the computer to control the receiver frequency selection, band designation and demodulation setting. The interface hardware and microcode cooperate to process and decode received signals according to cellular and paging network industry standards. An application running on the computer is provided which utilizes the processed signals to permit complete automated reception, display and storage of cellular, paging, and mobile radio data as well as the signal strength (RSSI) for each signal. All monitored activity is displayed on the PC screen and is written to a disk in an organized ASCII or HEX file for instant retrieval and analysis. Masks can also be specified by the user which allow only selected data to pass or not pass through the system. The masks may be used to trigger alarms and print data when selected data is detected.

Method of delivering paging messages using voice mail.

Abstract: Method and apparatus for delivering paging messages in a cellular communication system (10). The apparatus performs the method of paging (52) a portable communication unit (12), and upon the expiration of a paging period (58), converting the paging message into a voice mail message (60) for storage and later retrieval.

Method for the transmission of digital data in radio paging systems and corresponding radio paging receiver

Abstract: A method for the transmission of digital data elements including radio paging information elements, wherein the data elements are transmitted according to a technique of transmission implementing a plurality of orthogonal carrier frequencies (the COFDM technique), the signal being organized in frames comprising, firstly, at least one first channel called a fast information channel, comprising at least one symbol of data elements, the carrier frequencies of the symbols being modulated by data elements that are not temporally interleaved, and at least one second channel, called a main channel, comprising at least one symbol of data elements, the carrier frequencies of the symbols being modulated by data elements that are temporally interleaved beforehand, a frame number belonging to a set of predefined frame numbers being regularly inserted into the fast information channel, each of the radio paging receivers being assigned at least one of the frame numbers.

Improving the cache locality of memory allocation

Abstract: The allocation and disposal of memory is a ubiquitous operation in most programs. Rarely do programmers concern themselves with details of memory allocators; most assume that memory allocators provided by the system perform well. This paper presents a performance evaluation of the reference locality of dynamic storage allocation algorithms based on trace-driven simualtion of five large allocation-intensive C programs. In this paper, we show how the design of a memory allocator can significantly affect the reference locality for various applications. Our measurements show that poor locality in sequential-fit allocation algorithms reduces program performance, both by increasing paging and cache miss rates. While increased paging can be debilitating on any architecture, cache misses rates are also important for modern computer architectures. We show that algorithms attempting to be space-efficient by coalescing adjacent free objects show poor reference locality, possibly negating the benefits of space efficiency. At the other extreme, algorithms can expend considerable effort to increase reference locality yet gain little in total execution performance. Our measurements suggest an allocator design that is both very fast and has good locality of reference.

Scatter-gather in data processing system

Abstract: Described is a technique which finds use in transferring data between system memory which is arranged in pages and an attached storage system. In such a paged memory, data which crosses pages having contiguous virtual addresses may map to data which crosses discontiguous physical pages. Scatter-gather is advantageously employed in such a system in order to achieve the transfer data directly between memory and storage usually by Direct Memory Access (DMA). A secondary storage device which supports scatter-gather usually includes hardware which will perform the necessary calculations to transfer the data to and from the correct locations in physical memory. The technique of the present invention is useful with storage systems that do not support scatter-gather and comprises determining for each data transfer the identity of any requested sector which lies completely within a physical page and the identity of any sector which crosses boundaries between discontiguous physical pages; and for those sectors which lie within a physical page, transferring the sectors directly between secondary storage and memory by DMA; and for those sectors which cross said boundaries, transferring each sector to either the memory or secondary storage via an intermediate buffer.

Low-power frequency-hopped spread spectrum reverse paging system

Abstract: An acknowledgement paging system is described which fits within the existing infrastructure of a paging network and which provides low cost manufacture and low power operation while still enabling the acknowledgement paging over long distances. The acknowledgement paging system consists of a standard paging transmitter and a plurality of remote paging units which respond to a page using frequency-hopped spread-spectrum differential bi-phase shift keying communications. The plurality of pagers are assigned to groups with each group being assigned a separate starting location in a common, repeating pseudo-random noise code which determines the frequency hops. The grouping of pagers minimizes the collisions of acknowledgment transmissions between groups and the enables a large number of paging units to operate within a single geographic area. The pagers include a special double loop PLL synthesizer to produce an accurate narrow band frequency and to change or hop frequencies in a rapid fashion. The base receiving unit employs special algorithms for retrieving very low power acknowledgement paging messages in a noisy environment by using data redundancy, data interleaving, soft decoding and error correction codes to strip the bi-phase-modulated, frequency-hopped spread-spectrum digital data transmitted from the remote pocket pagers. A history of the frequency and phase drift is used during reception of the acknowledgement messages to predict the phase and frequency drift of the encoded digital information to further reduce decoding error. Signal to noise ratios are determined for each frequency hop and relatively noisy hops are discarded or minimized in a soft decoding process based redundancy of data bits.

Paging system with third party authorization

Abstract: A paging system with a number of central stations, each of which contains a number of pager apparatus associated with it. Each pager apparatus responds to one or more identifying numbers so that a caller may send a paging message to one or a number of pager apparatus, all of which respond to the same identifying number. The central station includes a profile of information for each pager apparatus associated with it. Paging information is comprised of various identification numbers to which the pager apparatus responds, as well as selected type of services. Pagers can additionally restrict receiving pagers from unwelcome callers, prioritize message, limit the number of received calls, and arrange for a transfer of their calls from one central station to another central station. Authorization can be required for a transaction. Means exist for billing for the processing and transmission of paging data on a per call basis. Verification of transmission or a transaction for billing purposes can be via a page or over the telephone network to the caller or to a third party.

Calendar driven selective call messaging system and operating method

Abstract: An electronic information processing device (300) capable of communicating a message to a paging terminal (112) uses an input device (309) to enter the message, select a messaging subscriber and their corresponding selective call address identifier, and schedule communication of the message to the paging terminal (112) for transmission to at least one selective call receiver corresponding to the selected messaging subscriber. The device uses a micro-controller (301) including at least one electronic memory (304, 305, 306) and a processor (303), to execute a program that controls operation of the device (300), maintain a registry of messaging subscribers (400) in the memory (304, 305, 306), and implement a real-time calendar for effecting communication of a selective call address identifier and corresponding message to the paging terminal (112) via a data port (308) in response to a scheduled communication of the message.

Radio paging system with voice transfer function and radio pager

Abstract: A radio paging system with voice transfer function for transmitting a voice message input from an ordinary push-button telephone set to a small-sized receive-only unsophisticated radio pager. A paging station is provided to transmit by radio the message from a telephone network to the radio pager as follows: voice information constituting the message is first converted from analog to digital format, compressed, stored in memory, and scrambled by a privacy function part for transmission. The radio pager in turn demodulates the received information, stores it in memory, retrieves a necessary message therefrom as designated, descrambles the designated message from scrambled state, expands the message from compressed state, and outputs the message as an audible output. In this manner, the user carrying the radio pager is able to get the message from the caller without the risk of being tapped by a third party.

Transponder system for localization of an object

Abstract: A transponder system is provided which presents a light weight portable or mobile system for localization of movable objects, e.g., for surveillance of valuable transports and the like. The small unit constituting the transponder contains a receiver (1) of paging type, a decoder (2), a logic unit (3), a transmitter portion (10), a built-in antenna and power supply (11). The system is controllable by an existing tested radio system for paging. One advantage of utilizing an already existing paging system is that functionality is well tested and a general covering range is obtained. In addition, costs for building up and operation of a paging system are eliminated. Control information being sent to the transponder includes a number of symbols defining a certain basic function for the built-in marker transmitter (10) and symbols which constitute control code and control data for the specific function. Consequently at least the frequency, transmit power and transmitting sequences of the marker transmitter are controllable.

Method and apparatus for coordinating clocks in a simulcast network

Abstract: A clock synchronization system for synchronizing a number of paging stations (24) with a system controller (23). Each paging station has a clock that includes a counter (52) that indicates the current local time and which is sequentially incremented by a counter advance signal applied thereto. A voltage controlled oscillator (58) generates the clocking signal that controls the advancement of the counter. A CPU (50) in the system controller monitors the time indicated by the counter and compares it to timing information received from a system clock. The timing information includes a time mark and a time mark send time. The system clock transmits to each paging system the time mark. At a future time, the system clock transmits the time mark send time which is the precise time at which the time mark was transmitted. The paging stations each measure the time interval between the time at which the time mark arrived and the time at which the time mark was transmitted by the system clock period. By subtracting the time at which the time mark was transmitted by the system clock and the propagation time to each paging station, each paging station can determine and correct the error in its clock.

Method for increasing battery life for selective call receivers

Abstract: A selective call receiver system (150, 200) includes a base site (150) which transmits paging information (100) having a plurality of batches (1-to-N). The base site (150) comprises timer (266) for calculating a time between a first of the at least two successive paging transmissions, and counter (266) for counting a number of batches to be transmitted in the at least two successive paging transmissions. A base site processor (254), coupled to the timer/counter (266), processes the paging information. The base site processor (254) comprises encoder (262) for encoding a portion of the first of the at least two successive paging transmissions with the calculated time and the number batches to be transmitted in the first paging transmission. A base site transmitter (252), coupled to the base site processor (254), transmits the at least two successive paging transmissions according to the calculated time to a plurality of selective call receivers (200). The selective call receiver (200) comprises a receiver (204) for receiving the paging transmissions. Decoder (206), coupled to the receiver (204)s, for decoding the number of batches (1-to-N) being transmitted therein and the time to a next paging transmission. Power switch (210), coupled the decoder, for disabling and enabling a power supply to the receiver (204) for receiving an assigned frame (F0-F7) of the plurality of batches (1-to-N). The power switch (210), being further responsive to the plurality of batches being decoded, disables and enables the power supply to the receiver for receiving successive paging transmissions.

Method of operating a combination radiotelephone and paging device

Abstract: A combined radiotelephone and paging device (101), hereinafter the combined unit, normally operates as a radiotelephone. In response to a predetermined condition, the combined unit operates as a paging device. The predetermined conditions include low battery voltage and poor communication channel quality or a request signal from a remote transceiver (109) of the radiotelephone system. The paging system and the radiotelephone system may be independent communication systems or they may be a single communication system. The combined unit (101) and its unique switching characteristics allows the combined unit (101) to utilize the paging devices beneficial qualities of lower power consumption and broader service range to enhance the usefulness of a radiotelephone.

User extendible voice transmission paging system and operating method

Abstract: A portable paging system communicates a paging message including a first portion having at least a selective call address (406) and a first activation code (407), and a second portion having a first segment (409) of an audio portion, to a selective call receiver (300). In the portable paging system, an input device (104) prompts an originator to request an extension of the second portion of the paging message, the extension including at least a second segment (410) of the audio portion. Upon receiving an affirmative talk time extension request from the originator, and if extending the second portion of the paging message does not exceed a predetermined number of extension requests or a predetermined total broadcast time allocated for the second portion of the paging message, a paging terminal controller (210) extends the second portion of the paging message.

The need for customizable operating systems

Abstract: Although modern operating systems provide powerful abstractions to application programs, they often fail to implement those abstractions in a way that provides applications programs, especially specialized application programs, with the best utilization of the physical resources of the computer system. The operating system community has implicitly recognized this problem by providing mechanisms that give client programmers more access to the physical substrate. The Mach External Pager allows clients to replace the paging mechanism. More recent work allows client replacement of the paging policy as well. Scheduler activations share the job of thread management between clients and the system. Apertos allows these and other aspects of operating system implementation to be client-controlled. Object-oriented operating systems under development also provide these kinds of control. We contend that there is a very general issue here, which operating systems have been among the first kinds of software to have to face head-on: some implementation decisions are crucial strategy decisions whose resolution will invariably bias the performance of the resulting implementation. Explicitly recognizing this issue helps to make sense of current trends and suggests new directions to explore. We consider the implications of this issue for operating systems, providing a framework with which to analyze systems such as those mentioned above, and suggesting connections with similar problems in other domains. >

System for removing section of memory from first system and allocating to second system in a manner indiscernable to both operating systems

Abstract: The functions of two virtual operating systems (e.g., S/370 VM, VSE or IX370 and S/88 OS) are merged into one physical system. Partner pairs of S/88 processors run the S/88 OS and handle the fault tolerant and single system image aspects of the system. One or more partner pairs of S/370 processors are coupled to corresponding S/88 processors directly and through the S/88 bus. Each S/370 processor is allocated from 1 to 16 megabytes of contiguous storage from the S/88 main storage. Each S/370 virtual operating system thinks its memory allocation starts at address 0, and it manages its memory through normal S/370 dynamic memory allocation and paging techniques, The S/370 is limit checked prevent the S/370 from accessing S/88 memory space. The S/88 Operating System is the master over all system hardware and I/O devices. The S/88 processors access the S/370 address space in direct response to a S/88 application program so that the S/88 may move I/O data into the S/370 I/O buffers and process the S/370 respective Operating Systems in a single system environment without significant rewriting of either operating system. Neither operating system is aware of the other operating system nor the other processor pairs.

Selective call receiver with battery saving features and method therefor

Abstract: A selective call receiver (200) includes a receiver (204) receiving paging signals including a preamble, a synchronization codeword, and at least address information. A controller (206) controlling a supply of power to the receiver for receiving the paging signals. A synchronization obtaining circuitry (404, 406, 224), coupled to the receiver (204), obtains synchronization to the paging signal. The synchronization obtaining circuitry (404, 406, 224) includes a baud rate detector and synchronization codeword detector, coupled to the baud rate detector, detects the synchronization codeword. An address decoder, responsive to the synchronization codeword being detected, decodes the address information. A synchronization maintaining circuitry (404, 408, 224) maintains synchronization to the paging signals during address decoding. The synchronization maintaining circuitry (404, 408, 224) includes circuitry for enabling the power switch (210) which enables the receiver (204) for receiving the paging signals. The baud rate detector (224), responsive to the power being supplied to the receiver (204), detects baud rate during at least first (150) and second (152) portions of the address. A preamble detector (404), responsive to the second portion of the address being received, detects preamble during at least a portion of a second address (152).

Adaptive bounded time windows in an optimistically synchronized simulator

Abstract: The authors address one problem of speeding parallel digital system simulation using time warp, namely, that logical processes with errant behavior can incur considerable rollback behavior (analogous to thrashing in paging virtual memories). Consequently, additional mechanisms must be added to an optimistically synchronized simulator to inhibit excessive rollback. They describe a method of adaptively sizing bounded time windows to balance lookahead processing. >

Method of remote launching applications in a message delivery system

Abstract: A first portable selective call receiver (130) updates a record in a database in the first portable selective call receiver, and automatically creates a message packet (200) in response to the record updating, the message packet (200) including message data (204) comprising changes updated to the record. The first portable selective call receiver (130) then sends the message packet (200) to a central paging communication system (100). The central paging communication system (100) receives the message packet (200), couples destination address information with the message packet (200) to provide a message, and wireless transmits the message over a paging communication channel. A second portable selective call receiver (130) receives the message from the paging communication channel, and updates a record in a database in the second portable selective call receiver (130) with the message data (204) from the message packet (200) from the received message.

Facsimile paging system with virtual display capability and method therefor

Abstract: A paging system includes a plurality of paging receivers (14, 16), each paging receiver having a display (19) for presenting the at least a portion of a representation of graphic information which substantially resembles at least a portion of graphic information received from a facsimile unit (11). The paging system further includes a paging terminal (13) capable of receiving graphic information received from the facsimile unit (11) and transmitting the representation of graphic information to the paging receiver (16).

The Mether System: Distributed Shared Memory for SunOS 4.0

Abstract: Mether is a Distributed Shared Memory (DSM) that runs on Sun1 workstations under the SunOS 4.0 operating system. User programs access the Mether address space in a way indistinguishable from other memory. Mether was inspired by the MemNet DSM, but unlike MemNet Mether consists of software communicating over a conventional Ethernet. The kernel part of Mether actually does no data transmission over the network. Data transmission is accomplished by a user-level server. The kernel driver has no preference for a server, and indeed does not know that servers exist. The kernel driver has been made very safe, and in fact panic is not in its dictionary. The Mether system supports a distributed shared memory. It is distributed in the sense that the pages of memory are not all at one workstation, but rather move around the network in a demand-paged fashion. It is shared in the sense that processes through the network share read, write, and execute access. And it is memory in the sense that user programs access the data in a way indistinguishable from other memory. The memory is never paged to disk, but the delay of accessing a page over the network is approximately the same as a paging disk. Two examples of Mether programs are shown in Figures 1 and 2. Note that, aside from the call to methersetup these programs look quite ordinary. One program prints out the value of the first 278 bytes of Mether memory; the other clears the first page of the Mether memory and then increments each byte 128 times. If the first program is running the values displayed increase. You can run either program on any host that supports Mether. The writer takes about 8 seconds to run, whether the watcher is running or not. In fact the writer usually runs a little faster if the watcher is on another machine. As the examples show, programs that access this memory can pretend that it is normal memory. If they do they may pay a substantial performance penalty. As shown in [4] programs that use DSM without modification rarely show the sort of performance gain found on a conventional sharedmemory multiprocessor. Programs must be more careful; if they are then they can communicate across the network at apparent memory speeds. The memory is accessed by opening a special file. Once the file is opened the user program executes an tnmap system call and maps the area into its address space. From that point on the process may treat the memory as it would any other memory. A function library is provided to make the use of Mether totally transparent. 'This work was done while the author was at University of Delaware, Newark, De. 'Sun and SunOS are trademarks of Sun Microsystems . I#include "uorld.hu main() C unsigned int i, j ; initscr() ; methersetup(); while(1) C move(0,O); for(i = 0; i > Figure 2: A program that writes to an Mether page If the process is the only one using an area of the memory, then it will run at full memory speed. If other processes on the same processor are using the same area, they will all run at full speed, unless one of the other processes locks an area of the shared memory. If processes on other processors simply read the memory infrequently there will be a small impact on writes as messages are sent out to the other processors invalidating their copy (or, in the current protocol, updating their copy). If many processors write the same location frequently then there will be a substantial performance degradation, probably only allowing a few thousand operations per second. Mether is non-blocking so the processor will not be slowed down, just the processes accessing the contended-for location. Mether is inspired by a high-speed memory-mapped network built at the University of Delaware by Delp and Farber. We give a cursory description of MemNet below; for more details see PI, [21 and PI. MemNet is a memory-mapped network. MemNet provides the user with (in the current implementation) a two Mb contiguous region of memory which is shared between a set of processors. The sharing is accomplished using dedicated page-managment hardware communicating via a highspeed token ring. When a MemNet page is needed and it is not present in the local interface a message is sent over the token ring requesting the page. The hardware provides consistency between pages. The algorithm used is similar to those used for snooping caches: when a chunk is written all other copies of that chunk are invalidated before the write completes. For performance reasons the pages are only 32 bytes long. This size was decided upon as the optimal tradeoff between transmission time and several other factors. For a complete performance analysis, see [I]. On a system such as MemNet the global address space is much larger than any single interface's memory. A problem that must be addressed is what to do in the event a chunk can not find an interface with room for it. Some interface must always keep the space open for that particular chunk (address) in the MemNet address space. To address this problem MemNet supports the notion of reserved memory. Reserved memory is the set of chunks for which a particular interface is responsible. Space will always be available for these chunks in the interfaces' reserved area. If no space can be found for a chunk on any interface in a non-reserved area, the chunk will end up back in the reserved memory in the interface which is its home. If MemNet did not support reserved memory, chunks might be lost as interfaces filled up with multiple copies of chunks. In general a MemNet interface will have a "fair share" (i.e. on a system with 10 interfaces, 10%) of its memory as reserved memory, with the rest of the memory available for other chunks. Mether supports reserved memory too, on a page basis. In fact, a page must be in the reserved memory of some Mether interface for it to be created. In other words, pages are created only from the reserved space, and only when they are referenced. When a non-reserved page is referenced for the first time on a processor, a request for that page is sent out. Only if that page is in some processor's reserved address space will space for it be allocated. One difference between MemNet and Mether is that Mether blocks the process when a page is unavailable whereas MemNet blocks the processor. This difference is more important than might at first seem. On MemNet, hot spots can consume the process, the network, and all the processors on the network. It is essential that algorithms be well-behaved. Otherwise the processors on the network can, in the absolute worst case, run orders of magnitude slower than normal. On Mether only the processes requesting the information are affected. Other processes, processors, and the network operate normally. We wanted to gain experience with a DSM that ran on more than the three processors available on the existing MemNet network. Our goal is to build a DSM that matches MemNets' best-case and worst-case performance. In the best case, MemNet runs at memory speeds; in the worst case, it is several orders of magnitude slower. One reason that Mether makes no attempt to minimize paging latency is that we want to get as close to the MemNet environment as possible and explore ways in which to use that environment correctly. We will describe Mether in further detail below, after which we will describe factors that constrained the design. Mether is driven by MemNet-inspired constraints; there were a number of other constraints, driven by both technical and political realities.

Radio paging system having a plurality of transmitter stations

Abstract: A global radio paging system in which a plurality of radio frequency carriers having the same frequency are synchronously modulated in a plurality of base stations corresponding in number to the radio frequency carriers with the same digital paging signal and transmitted, respectively. A paging controller which receives paging calls through a public switched telephone network stores preliminarily the maximum value of a sum of a paging request signal transmission time in a transmission line and a time required to process the paging request signal in each of the base stations and a high precision time signal is produced on the basis of a reference signal from a GPS (Global Positioning System) satellite. A transmission time assigning code is attached to the paging request signal, which assigns a time instance which is delayed from a current time determined by the high precision time signal by the maximum value of the sum of the transmission time and the processing tame as a transmission start time. In each of the base stations, a high precision time signal is produced on the basis of the reference time signal from the GPS satellite and the paging request signal supplied through the transmission line is processed on the basis of the high precision time signal to convert a format into the digital paging signal to thereby realize a synchronous modulation of the carriers.

Heat and Dump: competitive distributed paging

Abstract: This paper gives a randomized competitive distributed paging algorithm called Heat and Dump, The competitive ratio is logarithmic in the total storage capacity of the network, this is optimal to within a constant factor. This is in contrast to the linear optimal deterministic competitive ratio. >

Simulcast radio paging system.

Abstract: A global radio paging system is disclosed in which a plurality of radio frequency carriers having the same frequency are synchronously modulated in a plurality of base stations corresponding in number to the radio frequency carriers with the same digital paging signal and transmitted, respectively A paging controller which receives paging calls through a public switched telephone network stores (PSTN) preliminarily the maximum value of a sum of a paging request signal transmission time in a transmission line and a time required to process the paging request signal in each of the base stations and a high precision time signal is produced on the basis of a reference signal from a GPS (Global Positioning System) satellite In this paging controller, a transmission time assigning code is attached to the paging request signal The transmission assigning code assigns a time instance which is delayed from a current time determined by the high precision time signal by the maximum value of the sum of the transmission time and the processing time as a transmission start time On the other hand, in each of the base stations, a high precision time signal is produced on the basis of the reference time signal from the GPS satellite and the paging request signal supplied through the transmission line is processed on the basis of the high precision time signal to convert a format into the digital paging signal to thereby realize a synchronous modulation of the carriers

Geographic-area selective low-earth satellite-based paging broadcast system and method

Abstract: The present invention includes a low-earth satellite-based paging broadcast system (100) and method (200, 300) that maximizes spectral efficiency and minimizes power expenditure for the broadcast of paging messages by broadcasting the messages to terminator- or originator-selectable portions of the total system coverage area. The terminator selects a long-term preferred geographic area (LTPGA), and optionally, a short-term preferred geographic area (STPGA). The originator provides the terminator ID, the message, and optionally provides a customized preferred geographic area (CPGA). Terminators and originators can easily modify the selectable geographic areas (SGA(s)): LTPGA(s), STPGA(s), and CPGA(s). The gateway converts the SGA(s) to addressable coverage areas (ACA(s)), and transmits a signal including the paging information, and ACA(s) to at least a first communication satellite (COM SAT). The COM SAT(s) provide for crosslinking the signal to other COM SAT(s) and for broadcasting the paging information to the ACA(s).