Abstract: A light source drive which modulates a light source so as to cause the same to emit a light, includes: a superposition current generation part which generates a superposition current approximately corresponding to a charging/discharging current needed for a capacitance occurring in parallel to the light source for a predetermined time period near at least one of a rising-up part and a decaying-down part of a waveform of a drive current for the light source; and an addition/subtraction part which adds to or subtracts from the drive current the superposition current generated by the superposition current generation part.

Abstract: A disk changer for CD and DVD disks including a rotatable platter with several slots each adapted for receiving a disk generally needs two optical sensors. The first sensor is adapted for detecting the number of a related slot of the platter and for providing a stop signal for the rotation of the platter. The second sensor is adapted for detecting the presence or absence of a disk in a given slot. Said sensors and their associated evaluation circuits are expensive components. Therefore it is an object to simplify the means for realizing said sensors. Said second sensor has the form of a link (8) hingedly mounted between its two ends (10, 11) a first end (10) of the link (8) contacting the surface of the disk (4) and a second end (11) of the link (8) cooperating with said first optical sensor (6). By this solution said second sensor and its associated evaluation circuit can be omitted substantially reducing the total costs of the changer.

Abstract: A recording medium driving apparatus is provided. A signal from the tray position sensor 13 is provided to the connection point E to control a mute signal generator 80a in the driver IC. When the system controller is abnormal, the potential of the connection point E is low according to the signal from the tray position sensor 13, even though the HIGH signal is output on the buses 172, 75. The mute signal from the mute signal generator 80a is output, and the sled motor driver, the spindle motor driver and the solenoid driver for driving the solenoid 28b of the lock mechanism are maintained at the off state. Even though the system controller is abnormal, the sled motor and the lock mechanism of the tray are maintained at the non-driven state.

Abstract: An optical pick-up includes a lens holder and a lens holder supporting portion. The lens holder has a focusing coil, a tracking coil, and a pair of nickel plates arranged to sandwich the focusing coil from the top and the bottom. The lens holder supporting portion includes a pair of permanent magnets having their magnetic poles of the same polarity opposite to each other and sandwiching the lens holder as seen in two dimensions. A sidewall of a slide hole is pressed against a slide shaft. Thus, a disk drive which can suppress a jerky motion of the lens holder when it moves along the slide shaft with a simple mechanism is provided.

Abstract: An optical record carrier is described comprising a track for carrying data encoded in optical marks. A parameter of the track has a periodic variation for generating a varying signal when scanning the track, for example a variation of the center of a pre-groove usually called wobble. The track further comprises reference elements, e.g. headers, interrupting the periodic variation. The phase of the periodic variation after the reference elements is indicative of a property of the record carrier for controlling the scanning of the record carrier in dependence of said property. In particular the phase may indicate whether or not the bottom of the pre-groove is closer to the scanning beam entry side of the disc. Further a scanning device is described comprising a detector for detecting said phase based on the varying signal. The device adapts its scanning control means to the indicated property.

Abstract: A method and apparatus preventing a disc from being scratched by an objective lens. A focus pull-in operation is performed. If a level of a pull-in signal remains lower than a predetermined critical level for a predetermined critical period of time or more, the objective lens is controlled so as to move away from the disc.

Abstract: A bottom hold circuit generates a bottom hold signal (BH signal) from an RFDC signal from an RF amplifier, and sends it to a comparator. The comparator compares a reference level and the BH signal, and generates an Rfdet signal having H level if the BH signal was found to be lower than the reference level. The Rfdet signal is a signal having H level when a laser spot falls in a data-recorded area on an optical disk, and having L level when in a non-recorded area. When it was detected that Rfdet signal had H level throughout a single turn of the disk, a servo-processing microcomputer controls an optical pickup so as to apply tracking servo. This makes it possible to precisely detect a boundary position between the data-recorded area and non-recorded area. If the optical disk is decentered, the boundary area corresponded to the amount of decentering can successfully be isolated from the data-recorded area.

Abstract: When reproducing a multilayer optical disk using a high-numerical-aperture objective, the period of time required before the disk is reproduced is reduced by discriminating recording layers. A spherical aberration signal is detected as a differential signal between focus position fluctuation signals respectively in a central section and in a peripheral section of a reproduced flux of light. A recording layer is discriminated using a quantity of correction of spherical aberration at a zero-crossing point of a level or a spherical aberration signal associated with the differential signal. After adding the spherical aberration for the correction of the discriminated layer, residual spherical aberration is corrected by feedback control using a residual spherical aberration signal.

Abstract: A phase locked loop (PLL) for generating an oscillation signal such that the oscillation signal maintains a substantially constant phase difference with respect to a phase of a reference signal. The PLL includes a first frequency divider for dividing a frequency of the oscillation signal by a first divisor, and for generating a number of multiphase signals, such that each multiphase signal is out of phase with each of the other multiphase signals, a phase shift detection circuit for comparing a phase of the oscillation signal with the phase of the reference signal, and a phase adjusting circuit for selecting one of the multiphase signals generated by the first frequency divider to be an output signal such that the PLL is able to reduce the phase difference between the oscillation signal and the reference signal.

Abstract: A recording/producing device for writing data on a recording medium, or reading data from the recording medium, wherein data matching a recording pattern so specified as to include a plurality of mutually different sets of mark lengths and space lengths is written on the recording medium, and the data is then read to generate data signals. An edge shift detector uses data signals to measure the edge shift amount of a mark formed on a recording medium for each set of a mark length and a space length. A record controller sets a recording parameter for each set of a mark length and a space length based on the measured edge shift amount.

Abstract: A system and method for use in a data storage system which provides a combined phase lock loop (PLL) that utilizes a common Voltage Controlled Oscillator (VCO) and common integrator/loop-filter, but which is operational in a wobble-mode and a data-mode to provide most optimum operation and quick capture. Digital circuitry is primarily used in addition to the VCO and a loop-filter for acquiring frequency and phase lock while the optical disc drive is writing and reading. A digital Phase-detector for operation in the wobble-mode employs a down-counter that can be configured for both Frequency-Lock and Phase-Lock in a way that offers a large capture range and can adapt quickly to the multiple data-zones of the media-format.

Abstract: An optical information storage medium includes a lead-in area, a user data zone in which user data is recorded, and a lead-out area. Write protection information is recorded in at least one of the lead-in area and the lead-out area, together with defect management information. Information is recorded and/or reproduced according to the defect management information and the write protection information. The write protection information indicates a size of a write protected area differentiated from a plurality of sizes of write protected areas of the optical information storage medium.

Abstract: Four types of optical systems, a polarization optical system including an objective lens having a high numerical aperture, a polarization optical system including an objective lens having a low numerical aperture, a non-polarization optical system including an objective lens having a high numerical aperture and a non-polarization optical system including an objective lens having a low numerical aperture, are selectively used at the time of irradiating light from a semiconductor laser on a target disk for measurement, and the in-plane birefringence characteristic and perpendicular birefringence characteristic of the target disk are separately acquired based on the amounts of received light obtained by measuring reflected light from the target disk by a photosensor.

Abstract: A visible image forming method is performed for forming a visible image on an optical disk by an optical disk recording apparatus, which is designed for applying a laser beam onto an optical disk according to first recording data of a predetermined format to form pits having lengths specified by the first recording data. First, a generating step is performed for generating second recording data by embedding image formation data of a visible image in a part of a predetermined format which is the same as predetermined for the first recording data. Second, an extracting step is performed for extracting the image formation data of the visible image from the second recording data of the predetermined format. Then, a forming step is performed for forming pits in the optical disk according to the extracted image formation data so as to form the visible image on the optical disk.

Abstract: The present invention provides an optical recording medium in which two or more information-recording layers are laminated for obtaining a high recording density, and also incidence of light and detection of return light can be performed with high efficiency relating to an information-recording layer at a position distant from a light-incident side, thus having satisfactory recording and reproduction characteristics; and also provides an optical recording and reproducing method for performing at least recording or reproduction of information using this optical recording medium.

Abstract: A field emission device, which among other things may be used within an ultra-high density storage system, is disclosed. The emitter device includes an emitter electrode, an extractor electrode, and a solid-state field controlled emitter that utilizes a Schottky metal-semiconductor junction or barrier. The Schottky metal-semiconductor barrier is formed on the emitter electrode and electrically couples with the extractor electrode such that when an electric potential is placed between the emitter electrode and the extractor electrode, a field emission of electrons is generated from an exposed surface of the semiconductor layer. Further, the Schottky metal may be selected from typical conducting layers such as platinum, gold, silver, or a conductive semiconductor layer that is able to provide a high electron pool at the barrier.

Abstract: The present invention provides an optical pickup device comprises at least:

Abstract: The present invention relates to an optical pickup and a disc drive for preventing aberrations of laser light due to variations in temperature and humidity to ensure satisfactory characteristics of the laser light. A compound lens (14) is disposed in the optical path of the laser light, which is emitted by a light-emitting device (11) to be incident on a beam splitter (15), and in the optical path of the laser light, which exits from the beam splitter to be incident on a photodetector (13). The compound lens includes a diffractive section (23) for diffracting the laser light and a lens section (24) having a predetermined function for the laser light. The compound lens is formed by integrating individual sections including the diffractive section and the lens section. The compound lens is provided with a passage hole (14c) that lets in the laser light emitted by the light-emitting device to be incident on the beam splitter.

Abstract: An optical pickup device as integrated into a disk device which drives optical disks is described. To provide a highly-reliable optical pickup device: without attenuation of the power of the laser beam used to form a laser spot on the optical disk, accurately monitoring the amount of light emission from the semiconductor laser element, and unaffected by the nonuniform reflectance and permeability of the reflection film and by variations in environmental conditions such as temperature and humidity.

Abstract: An optical pickup device includes a housing having an upper-open recess, a plurality of optical components mounted at their predetermined positions in the recess of the housing, and a resin member capable of transmitting laser light, wherein the resin member is provided for covering the optical components and fixing them at their predetermined positions in the recess.

Abstract: A method for minimizing spherical aberration in an optical read/write drive caused by variances in lens thickness and laser wavelength. The method provides an economic solution that pairs objective lenses with laser diodes such that the spherical aberration caused by the objective lens is offset by the spherical aberration caused by the laser wavelength, thereby minimizing or completely canceling the overall spherical aberration.

Abstract: An optical pickup apparatus for reproducing information from an optical information recording medium or for recording information onto an optical information recording medium, is provided with a first light source for emitting first light flux having a first wavelength; a second light source for emitting second light flux having a second wavelength, the first wavelength being different from the second wavelength; a converging optical system having an optical axis and a diffractive portion, and a photo detector; wherein in case that the first light flux passes through the diffractive portion to generate at least one diffracted ray, an amount of n-th ordered diffracted ray of the first light flux is greater than that of any other ordered diffracted ray of the first light flux, and in case that the second light flux passes through the diffractive portion to generate at least one diffracted ray, an amount of n-th ordered diffracted ray of the second light flux is greater than that of any other ordered diffracted

Abstract: An optical pickup apparatus for reproducing information from an optical information recording medium or for recording information onto an optical information recording medium, is provided with a first light source for emitting first light flux having a first wavelength; a second light source for emitting second light flux having a second wavelength, the first wavelength being different from the second wavelength; a converging optical system having an optical axis and a diffractive portion, and a photo detector; wherein in case that the first light flux passes through the diffractive portion to generate at least one diffracted ray, an amount of n-th ordered diffracted ray of the first light flux is greater than that of any other ordered diffracted ray of the first light flux, and in case that the second light flux passes through the diffractive portion to generate at least one diffracted ray, an amount of n-th ordered diffracted ray of the second light flux is greater than that of any other ordered diffracted

Abstract: A multilayer optical disk including a plurality of information storage layers to/from which information is recorded and/or reproduced by an optical head. The plurality of information storage layers are stacked through intermediate layers and each information storage layer includes a wobbling track groove. The shape factors (amplitude of wobbling, depth of the track groove and/or slope angle of the side wall of the track groove, etc.) of the track groove of at least one information storage layer of the plurality of information storage layers are different from the shape factors of track grooves of other information storage layers. This allows a satisfactory signal to be reproduced from each information storage layer.

Abstract: Information indicative of disk-applicable recording speeds is incorporated in lead-out start time information within ATIP information that is recorded in pre-grooves located in a lead-in area of an optical disk. Once the optical disk is inserted in an optical disk recording device, the lead-out start time information is read out, so that recording is performed on the optical disk after a recording speed is automatically set to a highest settable speed value within a range specified by the read-out lead-out start time information. This arrangement can reliably prevent recording at speeds beyond predetermined limit values unique to the optical disk.

Abstract: A disc carrier assembly for a spindle motor for an optical disc drive includes a rotor and a disc carrier. The rotor includes an end wall and a peripheral wall. The end wall has a central hole. The disc carrier includes a main plate having an inner side and an outer side. The inner side of the main plate is in intimate contact with the end wall of the rotor. The main plate includes an engaging portion on the inner side thereof. The engaging portion includes an axial hole through which a shaft is securely extended, allowing joint rotation of the disc carrier and the shaft. The engaging portion further includes an annular groove for securely receiving a peripheral wall portion delimiting the central hole of the end wall of the rotor, allowing joint rotation of the disc carrier and the rotor.

Abstract: A record carrier provided with at least two parallel information layers (20, 21) suitable to be scanned by means of a single scanning head is described. Each information layer is provided with a control block (26, 31) in, which information is stored which can be used for reading the user information stored in this information layer. The control blocks are placed in the record carrier in such a way that they can be sequentially read by means of a scanning device, with a minimum displacement of the scanning head. The user information may be stored in a first format in the first information layer, and the same user information may be stored in a second format in a second information layer. The first format may be a low-density structure and the second format may be a high-density structure.

Abstract: Power control methods and apparatus for use in a sectorized cell of an OFDM communications system are described. Each sector of a cell uses the same frequencies and transmission times and is synchronized with the other sectors in the cell in terms of tone frequencies used at any given time and symbol transmission times. Tones are allocated to channels in each cell in the same manner so that each channel in a sector has a corresponding channel in another sector. Power differences between channels in different sectors are maintained to be within a pre-selected power difference. Different channels in a cell are assigned different power levels. Wireless terminals are assigned to channels based on channel feedback information. Wireless terminals with poor channel conditions are allocated to higher power channels than wireless terminals with good channel conditions. Lower power channels often include more tones per symbol time than high power channels.

Abstract: A system and methods are shown for providing packet data serving node (PDSN) redundancy. One exemplary method includes providing an access node with a plurality of packet data serving nodes and at least one system manager, establishing an N to 1 redundancy of active to standby PDSNs. Upon establishing a communications session with a mobile node, each active PDSN provides state updates to the standby PDSN including only non-recoverable data. Upon failure of any active PDSN, the standby PDSN reassigned as an active PDSN replacing the failed unit and assuming the communications session with the mobile node. The remaining active PDSNs are notified of the reassignment and transmission of updated state data is discontinued.

Abstract: A network system (10). The system comprises a first network node (MNx), and that node comprises an input (30IN) for receiving a packet, and the node also comprises a buffer (30LC), coupled to the input and for storing the packet. The first network node also comprises circuitry (50) for detecting when a number of packets stored in the buffer exceeds a buffer storage threshold and circuitry, responsive to a detection by the circuitry for detecting that the number of packets stored in the buffer exceeds the buffer storage threshold, for issuing a pause message (60) along an output to at least a second network node. The pause message indicates a message ingress address (602) and a message egress address (602), where that message ingress address and the message egress address correspond to a network ingress address and a network egress address in a congestion-causing packet received by the first network node.

Abstract: A method and system for offloading the transmission of large blocks of data from Transmission Control Protocol residing on a transmitting host computer to an intelligent network interface card (NIC) that schedules and performs transmittals. The NIC receives a pointer to the location of data to be transmitted, partitions the data into packets and writes sequence numbers in the headers of the packets. The NIC receives acknowledgements (ACKs) from the recipient system which contain a window size and beginning sequence number for the next transmittal. Provided the ACK indicates appropriate forward progress, the NIC continues to transmit until its buffer is empty. By allowing the NIC to process many packets in this fashion, significant burden is taken off the host computer system. In case of no forward progress, as evidenced by a duplicate ACK, or of an empty buffer, NIC returns control to the transmitting host computer for further action.

Abstract: A method of controlling data transmission in an Ethernet passive optical network (EPON) and an apparatus thereof are provided. Transmission permission messages using a mode of bandwidth allocation are queued in a queuing unit according to the types of the transmission permission messages. A transmission time duration of upstream data is defined for each of the transmission permission messages queued in the queuing unit. A bandwidth allocation unit generates transmission permission messages to allocate upstream data transmission bandwidth for an optical network unit (ONU), based on the transmission permission messages stored in the storage unit. A scheduler designates the predetermined priority, reads transmission permission messages from queues according to a predetermined priority, determines a transmission start time of upstream data, and outputs the transmission permission messages.

Abstract: A priority queuing apparatus and method for transmitting packets according to priority order of a packet are disclosed. The probability for selecting the output queue may vary according to the priority order of the output queue by means of the weighted linear feedback shift register (LFSR) employing a small number of flip flops and simple logic gates. In addition, the probability for selecting the output queue may be inversely proportional to the packet length by means of the weighted LFSR. The priority order of a packet may be reflected stochastically in the priority queuing operation by means of simple hardware configuration, and the packet length may be reflected in the priority queuing operation by means of simple hardware configuration.

Abstract: A terminal for uploading a program to a network node is provided. A request message generation unit generates a node information request message and the message is sent to a plurality of nodes on a communication path. Node information response messages are received from the plurality of the nodes and stored in a node information storage. An active node decision unit decides active nodes according to the node information response messages from the nodes and stores a list of the active nodes in an active node list storage. A program upload unit refers to the active node list and performs a process for uploading a predefined program stored in a program storage to each active node.

Abstract: An apparatus and method for designing a network are disclosed. The network is designed wherein nodes originate and terminate traffic to keep delay related to node-to-node delay-sensitive communication below a specified threshold. The method obtains an initial network topology including links and traffic routing based on a volume of traffic, allocates a maximum delay to each link in the network topology in proportion to the square root of an imputed cost for each link, sizes a bandwidth required for each link based on a current traffic routing and at least one of a maximum delay allocated to the link, determines link lengths and reroutes traffic according to shortest paths with respect to the determined link lengths.

Abstract: Wirelessly connected information handling system devices such as access points and end user devices are Layer 3 aware, particularly in respect to knowing the IP address of the stations wirelessly connected to them. With capability for full Layer 3 functionality, the use of Open Shortest Path First (OSPF) in these products provides a well tested, very robust method moving from a large flat LAN environment to the hierarchical world of IP routing.

Abstract: Methods and systems for triggerless screening of WMS messages for delivery with differential quality of service (QoS) are disclosed. Signaling messages are screened to determine whether they contain WMS content. In response to determining that a message contains WMS content, origination and/or destination party information is extracted from the WMS message to determine the QoS associated with the WMS message. The WMS message is then modified to include routing information for delivering the SMS messages to their intended destinations with different qualities of service.

Abstract: A traffic generating switch (1) has alternative operating modes, namely switching mode and traffic generation mode. The switch includes software modules (10), hardware modules (20), a buffer (30), and a plurality of communication ports (40). The software modules include a switch control module (12), a traffic generator control module (14), and a common platform (16). The switch control module is capable of receiving and forwarding packets, and the traffic generator control module is capable of generating instructions for traffic generation. The hardware modules include a forwarding device (22), a traffic generation device (24), and a media access controlling device (26). When the switch works under traffic generation mode, the traffic generator control module generates instructions for traffic generation according to parameters set by users.

Abstract: A method for routing communications in a communications system comprising a plurality of communication nodes, each node being capable of transmitting signals to and receiving signals from one or more other nodes, and including a first node, a second node and a plurality of other nodes; the method comprising selecting a route for communications from the first node to the second node by way of at least one of the other nodes on the basis of mobility characteristics and/or energy characteristics of each of the other nodes.

Abstract: Techniques to manage bandwidth using weighted reduction are described.

Abstract: The present invention is directed to the measurement of service levels provided by a communication network, including an Internet protocol communication network. In accordance with the present invention, test packets are sent from a first edge router across the communication network to a second edge router. The time required for the test packets to be transmitted across the communication network is then determined, and that time compared to the time specified by the governing service level agreement. A failure of the communication network to deliver test packets as guaranteed may be used as an indication that the service level agreement has been violated. Packet loss and packet jitter may also be measured and compared to levels guaranteed by the service level agreement. The present invention may be used to determine whether the delivery of data packets using requests for expedited service levels is necessary or desirable.

Abstract: A method for handling connection information in a communication network, including intercepting a data packet sent from/to a target, composing a header for the intercepted data packet, and sending the header to a monitoring entity. Instead of composing the header and forwarding it, the method may alternatively include examining the intercepted data packets with respect to specific information, determining whether an predetermined event with respect to the specific information has occurred, and, if the predetermined event has occurred, sending a corresponding message to a monitoring entity, thereby causing a more flexible handling of connection information.

Abstract: The invention relates to method for determining the power of signals transmitted by a radio transmission unit with several carriers over the air interface. In order to allow for a simple power detection of multicarrier signals, it is proposed that, while the air-interface is not used for data transmission, the method comprises: transmitting a modulated signal using a first carrier and determining its power; transmitting additionally a modulated signal using a further carrier; determining the total power of the sum of the modulated signals transmitted with said first and said further carrier, and determining the power of the modulated signal using said further carrier by subtracting the first determined power from the determined total power. The invention equally relates to a corresponding radio transmission unit and to a corresponding module for such a unit.

Abstract: A semiconductor device is fabricated using a micro-masking structure. The micro-masking structure is formed along the sidewalls of a trench in a semiconductor substrate or along the sidewalls of an electrode disposed over the semiconductor substrate. The micro-masking structure exposes portions of the sidewalls and covers other portions of the sidewalls. Then the exposed portions of the sidewalls are recessed to form a plurality of recesses such that the sidewalls have an increase surface area. After the recessing, the micro-masking structure is removed. The recessed sidewalls provide enhanced capacitance.

Abstract: To permit discovery and configuration of a remotely located network server element by a client element of a local network device, the client sends a multicast discovery protocol request packet. The server element may monitor packets received at a pre-configured discovery protocol port of the server for the discovery protocol request packet. When the discovery protocol request packet is received at the discovery protocol port, the server element may validate the discovery protocol request packet by comparing a portion of a header with a predetermined value, and may perform an action requested by the discovery protocol request packet. The server element may also unicast a discovery protocol reply packet to the client indicating a response to the requested action.

Abstract: An asymmetric modem communications system achieves high speed data transfers through a telephone network that includes both digital and analog communications mediums. In general, the system includes means for concurrently communicating first and second signals, respectively, in opposite directions along the connection between the communications devices and means for modulating the first and second signals with different modulation techniques. The communications occur in full duplex manner. In a possible implementation, a digital modem is interfaced to a digital network. The digital network is connected with a coder/decoder (codec). The codec is interfaced with a two-wire analog telephone connection, sometimes referred to as a copper loop. The telephone connection is interfaced with an analog modem. Both the digital and analog modems have a transmitter and a receiver.

Abstract: In a digital communication system such as a mobile radio system, fading distortion is compensated with a raised precision. In a transmitter, pilot signals are regularly inserted in the information signals. The amplitude of the pilot signals are set larger than the maximum possible amplitude of the information signals. The modulation scheme of the pilot signals may be different from that of the information signals. In a receiver, the fading distortion of each of the pilot signals is determined. The fading distortions of the information signals are estimated by interpolation using the determined fading distortion of the pilot signal, and then compensated. The frequency band of each information signal is preferably limited with a roll-off filter with a roll-off coefficient ranging from 0.1 to 0.4.

Abstract: Systems and methods are provided for routing voice communications to groups in a voice communication system. The voice communication system can be a mobile communication system having a plurality of members grouped as logical networks and/or unit task organizations. One or more routers are provided in the system. The one or more routers extract routing information from received voice messages. The routing information is used with a router database to determine which identified group to route the digitized voice packets. The one or more routers can be adapted to receive and route voice communications to different radio types across different logical networks.

Abstract: An apparatus and method for providing quality of service for the transmission of data packets from a base station in a wireless network to a plurality of mobile stations in a coverage area of the wireless network. The apparatus comprises a packet discriminator for receiving data packets from user devices requesting to transmit data packets to the mobile stations. The packet discriminator determines whether each data packet is a real time application or a non-real time application. The apparatus also comprises a real time traffic packet processor for receiving first selected data packets for real time applications, and a non-real time traffic packet processor for receiving second selected data packets for non-real time applications.

Abstract: A few high power tones used for synchronization and/or other purposes are transmitted in a FDM system during a period of time, e.g., a symbol transmission time period. During normal data transmission symbol periods signals are transmitted using at least 10 tones, e.g., per symbol time. Less than 5 high power signals are transmitted in a symbol time with at least 80% the maximum total transmitter power transmitted being allocated to the high power signals where the maximum total transmitter power is determined from a period of time which may includes one or more data and/or high power tone transmission periods. When the high power tones are transmitted at most 20% of transmitter power is available for transmitting other tones with the power normally being distributed among multiple tones. Normally some tones which would be transmitted in a symbol time go unused during transmission of the high power signals.