WO2014053565A2

WO2014053565A2 - Cable modem, receiving method, cable modem termination system and transmitting method

Info

Publication number: WO2014053565A2
Application number: PCT/EP2013/070577
Authority: WO
Inventors: Lothar Stadelmeier; Nabil Loghin
Original assignee: Sony Corporation; Sony Deutschland Gmbh
Priority date: 2012-10-02
Filing date: 2013-10-02
Publication date: 2014-04-10
Also published as: WO2014053565A3

Abstract

A cable modem for receiving signals transmitted within a transmission bandwidth by a cable modem termination system in a broadband communication system on the basis of a frame structure and a corresponding method are provided. Further, a cable modem termination system for transmitting signals within a transmission bandwidth for reception by a cable modem in a broadband communication system on the basis of a frame structure and a corresponding method are provided. A frame structure is used providing the ability to switch between active mode and sleep mode leading to power savings at the cable modem.

Description

CABLE MODEM, RECEIVING METHOD, CABLE MODEM TERMINATION SYSTEM AND

TRANSMITTED METHOD

BACKGROUND

Field of the Disclosure

[0001] The present disclosure relates to a cable modem for receiving signals transmitted within a transmission bandwidth by a cable modem termination system in a broadband communication system on the basis of a frame structure. Further, the present disclosure relates to a corresponding receiving method. Still further, the present disclosure relates to a cable modem termination system for receiving signals transmitted within a transmission bandwidth by a cable modem termination system in a broadband communication system on the basis of a frame structure and to a corresponding transmitting method. Still further, the present disclosure relates to a computer program and a non-transitory computer-readable recording medium. The present disclosure particularly relates to broadband communication systems and their elements that comply with the Data Over Cable Service Interface Specification (DOCSIS), including but not limited to DOCSIS-compliant cable modem communication systems. Description of Related Art

[0002] Conventional cable modem systems utilize DOC SIS -compliant equipment and protocols to carry out the transfer of data packets between multiple cable modems at the customer premises and a cable modem termination system (CMTS) at the cable headend. The term DOCSIS (Data Over Cable System Interface Specification) generally refers to a group of specifications published by CableLabs that define industry standards for cable headend and cable modem equipment. In part, DOCSIS sets forth requirements and objectives for various aspects of cable modem systems including operations support systems, management, data interfaces, as well as network layer, data link layer, and physical layer transport for data over cable systems, The most current version of the DOCSIS specification is DOCSIS 3.0.

[0003] An efficient way to save power especially on the cable modem (CM) side is seen as key feature for a further development of DOCSIS. The current version of DOCSIS is power inefficient since the complete signal needs to be constantly decoded by the cable modem even if there are currently no packets for this cable modem. Further, legacy DOCSIS systems use a dedicated control channel inside the continuously decoded transport stream which consumes a large power just to track the communicated signals.

[0004] The "background" description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventor(s), to the extent it is described in this background section, as well as aspects of the description which may not otherwise qualify as prior art at the time of filing, are neither expressly or impliedly admitted as prior art against the present disclosure.

SUMMARY

[0005] It is an object to provide a cable modem and a cable modem termination system for use in broadband communication systems, in particular DOC SIS -compliant communication systems that enables substantial power savings compared to current cable modems. It is a further object to provide a corresponding receiving method and a corresponding transmitting method as well as a corresponding computer program and a non-transitory computer-readable recording medium for implementing said receiving method and said transmitting method, respectively.

[0006] According to an aspect there is provided a cable modem for receiving signals transmitted within a transmission bandwidth by a cable modem termination system in a broadband communication system on the basis of a frame structure, said cable modem comprising:

a receiver that receives receive signals from said cable modem termination system; wherein said receive signals are provided in frames of said frame structure, a frame comprising one or more signaling patterns and one or more data patterns following the one or more signaling patterns in the time direction, wherein the one or more data patterns in a frame are respectively followed by further data patterns succeeding the one or more data patterns in the time direction, wherein signaling data including mode control data are arranged in each of said one or more signaling patterns in a frame and wherein data are arranged in said one or more data patterns and said further data patterns in a frame,

wherein said receiver is configured to be tuned to and to receive a reception bandwidth covering the complete transmission bandwidth or a selected part of said transmission bandwidth, wherein said reception bandwidth covers at least one data pattern to be received; and

a decoder that is configured to decode said mode control data, to switch between active mode and sleep mode based on the decoded mode control data, to decode, in the active mode, a signaling pattern and at least one data pattern covered by said reception bandwidth, and to decode, in the sleep mode, only a signaling pattern covered by said reception bandwidth.

[0007] According to a further aspect there is provided a cable modem for receiving signals transmitted within a transmission bandwidth by a cable modem termination system in a broadband communication system on the basis of a frame structure, said cable modem comprising: a receiver that receives receive signals from said cable modem termination system;

wherein said receive signals are provided in frames of said frame structure, a frame comprising more than one signaling pattern adjacent to each other in the frequency direction and one or more data patterns following the more than one signaling pattern in the time direction, wherein the one or more data patterns in a frame are respectively followed by further data patterns succeeding the one or more data patterns in the time direction, wherein signaling data including mode control data are arranged in each of said more than one signaling pattern in a frame and wherein data are arranged in said one or more data patterns and said further data patterns in a frame,

a decoder that is configured to decode said mode control data,

wherein said receiver is configured to switch between active mode and sleep mode based on the decoded mode control data and to reduce, when switching from active mode into sleep mode, the reception bandwidth to substantially the bandwidth of a single signaling pattern. [0008] According further aspects corresponding receiving methods are provided.

[0009] According to another aspect there is provided a cable modem termination system for transmitting signals within a transmission bandwidth for reception by a cable modem in a broadband communication system on the basis of a frame structure, said cable modem termination system comprising:

a frame former that forms frames of said frame structure, a frame comprising one or more signaling patterns and one or more data patterns following the one or more signaling patterns in the time direction, wherein the one or more data patterns in a frame are respectively followed by further data patterns succeeding the one or more data patterns in the time direction, wherein signaling data including mode control data are arranged in each of said one or more signaling patterns in a frame and wherein data are arranged in said one or more data patterns and said further data patterns in a frame,

wherein said mode control data is configured for being decoded by a cable modem and to cause said cable modem to switch between active mode and sleep mode based on the decoded mode control data, to decode, in the active mode, a signaling pattern and at least one data pattern covered by a reception bandwidth, and to decode, in the sleep mode, only a signaling pattern covered by said reception bandwidth; and

a transmitter that transmits transmit signals to one or more cable modems.

[0010] According to a further aspect there is provided a cable modem termination system for transmitting signals within a transmission bandwidth for reception by a cable modem in a broadband communication system on the basis of a frame structure, said cable modem termination system comprising:

a frame former that forms frames of said frame structure, a frame comprising more than one signaling pattern adjacent to each other in the frequency direction and one or more data patterns following the more than one signaling pattern in the time direction, wherein the one or more data patterns in a frame are respectively followed by further data patterns succeeding the one or more data patterns in the time direction, wherein signaling data including mode control data are arranged in each of said more than one signaling pattern in a frame and wherein data are arranged in said one or more data patterns and said further data patterns in a frame,

wherein said mode control data is configured for being decoded by a cable modem and to cause said cable modem to switch between active mode and sleep mode based on the decoded mode control data and to reduce, when switching from active mode into sleep mode, the reception bandwidth to substantially cover the bandwidth of a single signaling pattern; and a transmitter that transmits transmit signals to one or more cable modems.

[0011] According further aspects corresponding transmitting methods are provided.

[0012] According to still further aspects a computer program comprising program means for causing a computer to carry out the steps of the method disclosed herein, when said computer program is carried out on a computer, as well as a non-transitory computer-readable recording medium that stores therein a computer program product, which, when executed by a processor, causes the methods disclosed herein to be performed are provided.

[0013] Preferred embodiments are defined in the dependent claims. It shall be understood that the claimed receiving method, the claimed computer program and the claimed computer- readable recording medium have similar and/or identical preferred embodiments as the claimed cable modem or the claimed cable modem termination system and as defined in the dependent claims.

[0014] One of the aspects of this disclosure is to make use of the general layout of the frame structure (possible with one or more modified parameters, such as data slice bandwidth and carrier spacing) as used in multi-carrier broadcast systems that are compliant with the DVB-C2 (Digital Video Broadcasting for cable systems, 2^nd generation) standard as e.g. described in DVB Document A138, April 2009 "Digital Video Broadcasting (DVB); Frame structure channel coding and modulation for a second generation digital transmission system for cable systems (DVB-C2)", in particular section 9.1 of this document, or as described in US 2010/0195668 A2, which documents are herein incorporated by reference.

[0015] Further, the devices, systems and methods according the present disclosure are generally OFDM based, contrary to DOC SIS -compliant devices, systems and methods which are single carrier based up to DOCSIS 3.0. This allows for the proposed frame structure and the intended power savings.

[0016] Another aspect of this disclosure is to provide a power efficient phy (physical layer) based mechanism for cable modems to switch from active mode to sleep mode and vice versa. This is realized by using the (generally repeating) signaling data provided in the one or more signaling patterns (also called LI block symbols provided in a preamble of a frame) and by providing mode control data within said signaling data. These signaling data are included into the frames by the cable modem termination systems and decoded by the cable modems, where the information is used to switch between active mode and sleep mode. Thus, a significant power saving can be achieved in a cable modem compared to currently used cable modems, in particular DOC SIS -compliant cable modems, which do not have a dedicated mechanism to selectively go to sleep mode in modem idle times. This is particularly possible since generally a large number of cable modems receive transmission data from a cable modem termination system, i.e. since there is a multi-user transmission. At times when certain cable modems receive data, other cable modems that do not receive data can be put into sleep mode.

[0017] According to one embodiment, according to which the mode control data may be appropriately configured, during sleep times the cable modem only decodes the preamble, i.e. the one or more signaling patterns provided in the preamble, and not the payload part, i.e. the data patterns. The preamble contains signaling, i.e. the mode control data, that allows cable modems to switch from active mode to sleep mode and vice versa. Thus, decoding only the complete preamble or a portion of the preamble provides a significant contribution for power saving since, as an example, in sleep mode only a single preamble symbol (i.e. a single signaling pattern) needs to be decoded rather than 1 preamble symbol plus 448 data symbols (i.e. all the data patterns of the frame).

[0018] With respect to this embodiment it shall be noted that "decoding, in the sleep mode, only a signaling pattern covered by said reception bandwidth" shall be understood as meaning that only data from a signaling pattern are decoded in the sleep mode, but no data from any data patterns (or at least not a substantial amount of data from data patterns). Further, according to this embodiment the preamble may contain a single signaling pattern (covering the complete transmission bandwidth or a portion thereof) or more than one signaling pattern arranged adjacent to each other, e.g. two, three or more signaling patterns. In this case it may even be possible that the preamble comprises a real number (i.e. not necessarily integer number) of signaling patterns.

[0019] According to another embodiment, according to which the mode control data may be appropriately configured, during sleep times the reception bandwidth of the tuner (i.e. the receiver) is reduced to still allow the reception of at least one signaling pattern (also called one LI signaling block). This ensures that still all signaling information of the preamble is accessible while minimizing the power consumption, particularly due to the reduced reception bandwidth and, if present, ADC rate of an ADC (analog to digital converter). This measure thus provides another significant contribution for power saving. The measure of both these embodiments can be used in combination in cable modems and cable modem termination systems providing an even further increase power saving.

[0020] With respect to this embodiment it shall be noted that "reducing the reception bandwidth to substantially the bandwidth of a single signaling pattern" shall be understood as meaning that either a complete signaling pattern is received or that two portions of adjacently arranged signaling patterns are received and combined into a complete signaling pattern to obtain signaling data of a complete signaling pattern for subsequent decoding. Further, according to this embodiment the preamble contains more than one signaling pattern arranged adjacent to each other, e.g. two, three or more signaling patterns. In this case it may even be possible that the preamble comprises a real number (i.e. not necessarily integer number) of signaling patterns.

[0021] It is to be understood that both the foregoing general description of the disclosure and the following detailed description are exemplary, but are not restrictive of the disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

[0022] A more complete appreciation of the disclosure and many of the attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, wherein:

Fig. 1 shows schematic diagram of an entire transmission bandwidth from which a selected part can be selectively and flexibly received,

Fig. 2 shows an example for a segmentation of the overall transmission bandwidth,

Fig. 3 shows a schematic time domain representation of a frame structure according to the present disclosure,

Fig. 4 shows a schematic example of a frame structure or pattern according to the present

disclosure,

Fig. 5 shows a schematic diagram of a broadband transmission system according to the present disclosure,

Fig. 6 shows a diagram illustrating the frame structure as proposed according to DVB-C2,

Fig. 7 shows a diagram illustrating a frame structure as proposed according to DVB-C2 with adjusted carrier spacing,

Fig. 8 shows a schematic diagram of an embodiment of a receiver as used in a proposed cable modem,

Fig. 9 shows a block diagram of a proposed cable modem termination system,

Fig. 10 shows a block diagram of a proposed cable modem,

Fig. 1 1 shows a proposed frame structure to illustrate a first embodiment of the proposed devices and methods, Fig. 12 shows a proposed frame structure to illustrate a second embodiment of the proposed devices and methods,

Fig. 13 shows a proposed frame structure to illustrate a third embodiment of the proposed devices and methods,

Fig. 14 shows a potential implementation of a frame structure according to the present disclosure,

Fig. 15 shows another potential implementation of a frame structure according to the present disclosure,

Fig. 16 shows a part of the frame structure of Fig. 4 to illustrate the reconstruction of a signalling pattern, and

Fig. 17 shows a schematic diagram of a processing system embodying aspects of this disclosure.

DESCRIPTION OF THE EMBODIMENTS

[0023] Before details of the present disclosure will be explained with reference to embodiments of the disclosure, the basic details of multi-channel broadcast system in accordance with the DVB-C2 standard shall be explained, as e.g. described in US 2010/0195668 A2 since some of these details will also be applied in embodiments of the present disclosure.

[0024] Referring now to the drawings, wherein like reference numerals designate identical or corresponding parts throughout the several views, Fig. 1 shows a schematic representation of an entire transmission bandwidth 1 , in which a DVB-C2 compliant or at least part DVB-C2 similar transmitting apparatus (here a CMTS) transmits signals in a multi-carrier system. In a cable television environment, the entire transmission bandwidth 1 could e.g. refer to a bandwidth in which digital television signals are transmitted to one or more recipients and could e.g. have a bandwidth of 64 MHz or any other suitable bandwidth. The transmission bandwidth 1 could hereby be part of a larger medium bandwidth within which different kinds of signals are transmitted via the respective wireless or wired transmission medium. In the example of cable television, the medium bandwidth could e.g. extend from (almost) 0 MHz to 862 MHz (or even higher) and the transmission bandwidth 1 could be a part of it. Fig. 1 further schematically shows a block diagram of a receiving apparatus 3 (here a CM), which is adapted to be tuned to and selectively receive a selected part 2 of the transmission bandwidth 1 which part 2 may generally also be the complete transmission bandwidth 1. Hereby, the receiving apparatus 3 comprises a tuner 4 (the "receiver" of a CM) which is adapted to be tuned to and selectively receive the wanted part 2 of the transmission bandwidth 1 as well as further processing means 5 (in particular a decoder) which perform the further necessary processing of the received signals in line with the respective communication system, such as a demodulation, channel decoding and the like. [0025] As stated above, the present disclosure enables a flexible and changing reception of a wanted part 2 of the transmission bandwidth 1 in a receiver by providing a specific and new frame structure for a multi-carrier system. Fig. 2 shows a schematic representation of an overall transmission bandwidth 1 (e.g. 32MHz, 64MHz or any other suitable number), within which a transmitting apparatus is adapted to transmit data content, such as video data, audio data or any other kind of data, in different segments or parts 6, 7, 8, 9 and 10. For example, the parts 6, 7, 8, 9 and 10 could be used by the transmitting apparatus to transmit different kinds of data, data from different sources, different data streams, data intended for different recipients and so forth. Further, per part data for different recipients can be transmitted. The parts 6, 8 and 9 have for example a maximum bandwidth, i.e. the maximum bandwidth which can be received by a corresponding receiving apparatus (e.g. 8MHz or 7.61MHz or any other suitable number). The parts 7 and 10 have smaller bandwidths.

[0026] A frame structure or pattern is applied to the entire transmission bandwidth 1 whereby each frame comprises at least one signaling pattern, preferably at least two signaling patterns adjacent to each other in the frequency direction, and a number of data patterns. Each signaling pattern preferably has the same length and comprises first signaling data as well as pilot signals mapped onto its frequency carriers (frequency subcarriers in the case of an OFDM system). In other words, the overall transmission bandwidth 1 is preferably divided into equal parts for the signaling patterns, whereby the maximum bandwidth to which a receiver can be tuned, for example the bandwidth shown for parts 6 and 9 in Fig. 2, has to be equal or larger than the length of each signaling pattern. The frame structure may therefore only comprise signaling patterns and data patterns. In other words, the frame structure comprises a preamble which only comprises one or more signaling patterns, and with data patterns following the preamble in the time direction.

Alternatively, the signaling patterns could not have pilot signals, but could be preceded by training patterns with pilot signals. It should be noted that the length of the various data parts in the transmission bandwidth cannot exceed the length (number of frequency carriers) of the maximum reception bandwidth to which a receiver can be tuned.

[0027] Fig. 3 shows a schematic representation of an example of a time domain structure of frames 1 1 , 1 , 11 ". Each frame 1 1 , 1 Γ, 11 " comprises a preamble 12, 12', 12" (including one or more signaling symbols) and several data symbols 14, 14^'. Hereby, in the time domain, the signaling symbols are preceding the data symbols. Each frame 1 1 , 11 ', 1 1 " may have a plurality of data symbols, wherein systems are possible in which the number of data symbols in each frame 11 , 1 1 ', 11 " varies. The pilot signals comprised in the signaling symbols are used in a receiving apparatus to perform channel estimation and/or integer frequency offset calculation as well as detection of the beginning of a frame (the beginning of a frame in the frequency as well as in the time direction can be detected). The time synchronization can e.g. be done by performing a guard interval correlation (or any other suitable technique) on guard intervals of received signaling symbols and/or data symbols in the time domain. The signaling symbols further contain signaling information, for example all physical layer information that is needed by the receiving apparatus to decode the received signals, such as but not limited to LI signaling data.

[0028] The signaling data may for example comprise the allocation of data content to the various data patterns, i.e. for example which services, data streams, modulation, error correction settings etc. are located on which frequency carriers, so that the receiving apparatus can obtain information to which part of the entire transmission bandwidth it shall be tuned. It is possible that all signaling patterns in a frame contain the identical signaling data. Alternatively, each signaling pattern may (additionally) contain signaling data indicating the offset or distance of the respective signaling pattern from the beginning of a frame so that the receiving apparatus may optimize the tuning to the wanted part of the transmission frequency in a way that the receipt of the signaling patterns and the data patterns is optimized. On the other hand, the offset or distance of the respective signaling pattern from the beginning of a frame can also be encoded in pilot signals, in pilot signal sequences or in guard bands allocated to or comprised in the signaling patterns, so that every signaling pattern in one frame can have the identical signaling data. The use of the frame structure has the further advantage that by dividing the data stream into logical blocks, changes of the frame structure can be signaled from frame to frame, whereby a preceding frame signals the changed frame structure of the or one of the succeeding frames. For example, the frame structure allows a seamless change of modulation parameters without creating errors.

[0029] Fig. 4 shows a schematic example of a frequency domain representation of a frame structure or pattern 29. The frame structure 29 covers the entire transmission bandwidth 24 in the frequency direction and comprises at least two (or at least three, or at least four, etc) signaling patterns 31 adjacent to each other in the frequency direction, each carrying the identical or almost identical first signaling data mapped on respective frequency carriers and having the same length. In the example shown in Fig. 4, the first time slot of the entire transmission bandwidth 24 is sub-divided into four signaling patterns 31 , but any other higher or lower number of signaling patterns might be suitable.

[0030] The frame structure or pattern 29 further comprises one or more data pattern(s) or segment(s) extending over the entire or a part of the frequency bandwidth 24 in the frequency direction and following the signaling patterns 31 in the time direction. In the time slot immediately following the time slot in which the signaling patterns 31 are located, the frame structure 29 shown in Fig. 4 comprises several data patterns 32, 33, 34, 35, 36 and 37 with different lengths, i.e. a different number of respective frequency carriers onto which data are mapped. The frame structure 29 further comprises additional data segments in succeeding time slots, whereby the additional data patterns respectively have the same length (in frequency direction) and number of frequency carriers as the respectively preceding data pattern. For example, the data patterns 32', 32", 32"' and 32" " have the same length as the first data pattern 32. The data patterns 33', 33 ", 33 "' and 33 "" have the same length as the data pattern 33. In other words, the additional data patterns have the same frequency dimension structure as the several data patterns 32, 33, 34, 35, 36 and 37 in the first time slot after the signaling patterns 31. Thus, if the receiving apparatus for example tunes to a part 38 of the transmission bandwidth in order to receive the data pattern 35, all time wise succeeding data patterns 35 ', 35 ", 35' " and 35' "' which have the same length as the data pattern 35 can be properly received until the next frame.

[0031] In the transmitting apparatus, a frame former is adapted to arrange the signaling data (obtained from a modulating means) as well pilot signals (supplied from a suitable means within the transmitting apparatus) in each signaling pattern. The signaling data are beforehand modulated by the modulating means with a suitable modulation scheme, e.g. a QAM modulation or any other. Advantageously, a pseudo noise sequence (e.g., pseudo-random binary sequence, PRBS) or a CAZAC sequence, or the like is used for the pilot signals, but any other pilot signal sequence with good pseudo noise and/or correlation properties might be suitable. Each signaling pattern of a frame might comprise a different pilot signal sequence, but alternatively, the pilot signals of the signaling pattern of one frame might form a single pilot signal sequence.

[0032] Further details and advantageous embodiments, particularly of the frame structure, which may also be applied according to the present disclosure, can be found in US

2010/0195668 A2.

[0033] Common to all DOC SIS -compliant broadband data communication architectures is the transfer of data between a central location and many remote subscribers over a shared communications medium. The terms used to describe the central location vary depending on the type of communication architecture: for example, in cable modem systems, the central location is typically referred to as the headend (i.e. the cable modem termination system, CMTS) in broadband terrestrial fixed wireless systems, it is typically referred to as a wireless access termination system (WATS), and in two-way satellite communication systems, it is typically referred to as the satellite gateway. Terms used to describe subscriber equipment also vary depending on the type of communication architecture: for example, in cable modem systems, such equipment is typically referred to as a cable modem (CM), in broadband terrestrial fixed wireless systems, it is typically referred to as a wireless modem (WM), and in two-way satellite communication systems, it is typically referred to as a satellite modem (SM).

[0034] For the purposes of the description provided herein, terminology pertaining to cable modem systems will be used. However, as will be appreciated by persons skilled in the relevant art based on the teachings provided herein, the present disclosure is not limited to cable modem systems, and may be implemented, for example, in any DOCSIS-compliant or EPOC- compliant broadband communication system (EPOC being a multitasking operating system developed by PSION to run its PDA products).

[0035] Fig. 5 shows basic elements of an example DOCSIS-compliant cable modem system 100 (i.e. a broadband communication system) as disclosed in US 2012/0008539 Al in which an embodiment of the present disclosure may operate. In example system 100, a cable network 106, which typically comprises a hybrid fiber-coaxial (HFC) network, provides a point-to- multipoint topology for supporting the communication of data, such as ΓΡ packets, between a cable modem termination system (CMTS) 104 at the cable headend and multiple cable modems (CM) 108a-108n at various customer premises. As will be appreciated by persons skilled in the relevant art(s), CMTS 104 operates, in part, as an interface between cable network 106 and a wide area network (WAN) 102, and each of cable modems 108a-108n operates as an interface between cable network 106 and at least one corresponding customer premises equipment (CPE) 110a- 110^η. Communication from CMTS 104 to cable modems 108a-108n is customarily referred to as "downstream" communication, and communication from cable modems 108a-108n to CMTS 104 is customarily referred to as "upstream" communication. The present disclosure is referring to the downstream communication.

[0036] Fig. 6 depicts the existing DVB-C2 frame structure with the conventional carrier spacing. A frame structure with an adjusted carrier spacing is depicted in Fig. 7.

[0037] Broadband transmit (Tx) signals are in general beneficial for efficiency and flexibility, but the receiver complexity should be limited. The adopted solution in DVB-C2 (or segmented OFDM in general) is to extract a set of subcarriers out of a broad transmit spectrum. This becomes possible since the OFDM symbol duration is independent from Tx channel bandwidth. This is applicable to every OFDM system, no extra measures are required. As a result, different reception bandwidths become possible, which is the base for scalable cable modem classes, in particular DOCSIS-compliant cable modem classes.

[0038] An efficient way to save power especially on the side of the cable modem is desired. Today's DOCSIS is power inefficient, since the whole signal needs to be constantly decoded by the cable modem even if there are currently no packets for this cable modem. There is no dedicated mechanism to selectively go to sleep mode in modem idle times. Further, legacy DOC- SlS-compliant systems use a dedicated control channel inside the continuous decoded transport stream which consumes huge power just to track the traffic.

[0039] Upcoming silicon tuner architectures allow variable bandwidths: Multiples of a common bandwidth are realized just by rescaling the ADC (Analog to Digital Converter) (over)- sampling rate and digital filtering (it shall be noted that multiples are most reasonable, however fractional relations between ADC rates are generally possible, too). The final reception (tuner) bandwidth is determined by an (over-) sampling rate of the ADC. Multiples of a standard bandwidth are therefore possible.

[0040] Fig. 8 depicts a schematic diagram of a tuner (receiver) 200 as a particular realization of a tuner 4 (shown in Fig. 1). The tuner 200 comprises a broadband preselection filter 202, a LNA (Low Noise Amplifier) 204, a mixer 206, a LO (Local Oscillator) 208, a filter 210, an ADC 212 and an OFDM demodulator 214. Naturally, the power consumption of the tuner 200 as well as the following demodulator depends on the selected tuning bandwidth (i.e. ADC rate). Significant power savings can be achieved if the ADC rate as well as the demodulator decoding clock is reduced.

[0041] Further power savings could be achieved by calculating an FFT of reduced size. In still another embodiment the reception bandwidth could be maintained, but the preamble (containing repetitions of signaling data) is demodulated more often. The symbols of the demodulated preamble could then be combined thus receiving more reception power so that power can be saved in other components, e.g. by reducing the amplification factor of the LNA 204 or switching it off (or leaving it out completely).

[0042] The idea of this disclosure is to provide a power efficient phy based mechanism for cable modems to switch from active mode to sleep mode and vice versa. This is realized by using the LI block sequence in the preamble to achieve significant power saving of the cable modem.

[0043] A broadband communication system according to the present disclosure is generally designed as shown in Fig. 5. It comprises one or more cable modem termination systems for transmitting signals within a transmission bandwidth for reception by a cable modem in the broadband communication system on the basis of a frame structure and one or more cable modems for receiving signals transmitted within said transmission bandwidth by the cable modem termination system. [0044] A first preferred embodiment of a cable modem termination system 300 for transmitting signals within a transmission bandwidth for reception by a cable modem in a broadband communication system on the basis of a frame structure according to the present disclosure is depicted in Fig. 9. The cable modem termination system 300 comprises at least a frame former 302 that forms frames of said frame structure and a transmitter 304 that transmits transmit signals to one or more cable modems. Further elements of a cable modem termination system 300 that are generally provided in practical implementations are not shown here for clarity's sake.

[0045] A frame formed by the frame former 302 comprises one or more signaling patterns and one or more data patterns adjacent to each other in the frequency direction and following the one or more signaling patterns in the time direction, wherein the one or more data patterns in a frame are respectively followed by further data patterns succeeding the one or more data patterns in the time direction, wherein signaling data including mode control data are arranged in each of said one or more signaling patterns in a frame and wherein data are arranged in said one or more data patterns and said further data patterns in a frame. The mode control data is configured for being decoded by a cable modem and to cause said cable modem to switch between active mode and sleep mode based on the decoded mode control data, to decode, in the active mode, a signaling pattern and at least one data pattern covered by said reception bandwidth, and to decode (per frame), in the sleep mode, only a signaling pattern (i.e. a single complete signaling pattern or two portion from two adjacent signaling pattern that are combined into one complete signaling pattern) covered by said reception bandwidth.

[0046] A first preferred embodiment of a corresponding cable modem 310 for receiving signals transmitted within the transmission bandwidth by a cable modem termination system 300 in a broadband communication system on the basis of the above described frame structure according to the present disclosure is depicted in Fig. 10. The cable modem 310 comprises a receiver 312 that receives receive signals from said cable modem termination system and a decoder 314. The receive signals are provided in frames of said frame structure. The receiver 312 is configured to be tuned to and to receive a reception bandwidth covering the complete transmission bandwidth or a selected part of said transmission bandwidth, wherein said reception bandwidth covers at least one data pattern to be received. The decoder 314 is configured to decode said mode control data, to switch between active mode and sleep mode based on the decoded mode control data, to decode, in the active mode, a signaling pattern and at least one data pattern covered by said reception bandwidth, and to decode, in the sleep mode, only a signaling pattern covered by said reception bandwidth. Preferably, one or more elements of the cable modem are thus put into sleep mode (e.g. completely switched off), such as the further processing means 5 shown in Fig. 1 or one or more elements of the tuner shown in Fig. 8) to save power.

[0047] A second preferred embodiment of a cable modem termination system according to the present disclosure generally has the same layout as the cable modem termination system 300 shown in Fig. 9. However, according to said second embodiment the mode control data is configured for being decoded by a cable modem and to cause said cable modem to switch between active mode and sleep mode based on the decoded mode control data and to reduce, when switching from active mode into sleep mode, the reception bandwidth to substantially the bandwidth of a single signaling pattern.

[0048] A second preferred embodiment of a corresponding cable modem according to the present disclosure generally has the same layout as the cable modem 310 shown in Fig. 10. However, according to this second embodiment the decoder 314 is configured to decode said mode control data and the receiver 312 is configured to switch between active mode and sleep mode based on the decoded mode control data and to reduce, when switching from active mode into sleep mode, the reception bandwidth to substantially the bandwidth of a single signaling pattern.

[0049] In a preferred embodiment the bandwidth of a data slice (which comprises one or more data patterns having the same frequency direction structure) is a multiple of a minimum bandwidth, e.g. 24MHz. This means that data slices can e.g. allocate 24MHz, 48MHz, 72MHz, 96MHz ... 192MHz and can exceed the LI block (= signaling pattern) bandwidth. The LI block bandwidth is e.g. chosen accordingly to 24MHz. During sleep mode periods the cable modem reduces its reception bandwidth to the minimum, i.e. LI decoding bandwidth (in this example: 24MHz) with a 12.5kHz carrier spacing.

[0050] In a preferred embodiment the tuning frequency is kept during sleep mode. This embodiment ensures fastest possible tracking to the target data pattern after reacquisition (i.e. in the active mode after wake up). Fig. 11 illustrates a frame 400 having a preamble 402 and a payload portion 404. The preamble 402 comprises a number of subsequently arranged LI blocks 403, which, in this embodiment, comprise identical signaling data and have the same size in time and in frequency direction. The payload portion 404 comprises four data slices 405, 406, 407, 408 each comprising one or more data patterns.

[0051] As illustrated in Fig. 11 A the first data slice 405 having an exemplary bandwidth of 72MHz is decoded during active mode, which, in this embodiment, is a broadband operating mode. The receiver (frontend) of the cable modem is set to receive this bandwidth and the decoder is set to decode this bandwidth. As soon as the cable modem is asked or decides by use of the mode control information to change to sleep mode, the reception bandwidth is reduced to the LI block bandwidth as illustrated in Fig. 1 IB. In this embodiment only the particular LI block 403a is decoded, but not any data pattern from the data slice 405.

[0052] The signaling data inside the LI block 403a comprises mode control data, e.g. a mode trigger, mode flag or switching time indicator indicating the time of switching between active mode and sleep mode for a particular CM or a group of CMs.

[0053] Preferably, the receiver is configured in this embodiment to change, when switching from sleep mode into active mode, the reception bandwidth to the previous reception bandwidth used before switching from active mode into sleep mode or to a reception bandwidth defined in a decoded signaling pattern. For instance, before the sleep mode a narrowband phone call is handled and after the sleep mode a broadband web session is handled. The allocated bandwidth may be signaled in the LI block (or in a separate control channel).

[0054] It should be noted that although Fig. 11 implies that the tuning positions must map to the LI block raster, this is generally not required, as arbitrary tuning positions are possible for the receiver of the cable modem due to the repetitive structure of the LI blocks.

[0055] In another preferred embodiment the tuning frequency is changed to the center frequency (or another defined location) when switching to the sleep mode. Fig. 12 illustrates a frame 500 having basically the same elements as the frame 400 shown in Fig. 11. In addition, an optional control channel pattern 410 (i.e. additional signaling data) is provided in an initial portion of a data slice, here the second data slice 406. The optional control channel pattern 410 is provided at the center frequency of the frame 500 (or the defined location to which the tuning frequency is switched during sleep mode). Thus, additional control capacity is provided in the middle of the complete bandwidth that can be read out during sleep mode.

[0056] As shown in Fig. 12A the first data slice 405 with a bandwidth of e.g. 72MHz is decoded during active mode. The decoder (frontend) is set to decode this bandwidth. As soon as the cable modem is asked (or decides by itself) to fall to sleep mode, the reception bandwidth is reduced to the LI block bandwidth and the tuning position is changed to its center position as shown in Fig. 12B and only the LI block 403b and, optionally, the control channel pattern 410 is decoded.

[0057] Said additional signaling data can be used if there is not sufficient capacity (or if capacity shall be saved) in the preamble for transmitting all required signaling data. The signalling data in the preamble could then simply include a pointer to the control channel pattern 410 comprising e.g. cable modem specific signaling data. Further, the preamble could simply comprise a kind of trigger that a mode shall be changed for selected or all cable modems. The exact information about the change of the mode is then signaled in the control channel pattern 410. Still further, the additional signaling data can be used to embed specific commands, e.g. DOCSIS- specific MAC commands (e.g. MAP messages) that control the scheduling in the upstream data transmission.

[0058] In still another preferred embodiment illustrated in Fig. 13 the position of the control channel pattern 411 is signaled in the preamble 402 so that the control channel pattern 411 needs not to be located in the center position of the frame. As shown in Fig. 13 A the first data slice 405 with a bandwidth of e.g. 72MHz is decoded during active mode. The decoder (frontend) is set to decode this bandwidth. As soon as the cable modem is asked (or decides by itself) to fall to sleep mode, the reception bandwidth is reduced to the LI block bandwidth and the tuning position is changed to the position of the control channel pattern 41 1 as shown in Fig. 13B and only the LI block 403c and, optionally, the control channel pattern 411 is decoded. Thus, the control channel pattern 411 (or several control channel patterns) can be located in any data slice. The location of the control channel can be extracted from the signaling data decoded from the LI block 403c or any other LI block(s) 403 in the preamble 402.

[0059] For all embodiments shown in Figs. 11 to 13 the cable modem generally restores its original tuning position after it returns to regular operation mode (active mode). Alternatively the mode control data can include new decoding parameters, e.g. a new tuning frequency, reception bandwidth, ModCod (i.e. modulation and coding parameter), etc.

[0060] In an embodiment it is provided that the cable modem, at least the decoder and/or receiver, is woken up one (or more) frame(s) prior to actual start of data traffic in order to provide enough time to perform required steps such as synchronization, channel estimation, offset compensation etc. This is e.g. initiated by the MAC layer above, i.e. the MAC layer inserts the mode control data in the preamble and schedules the traffic to start in the next frame.

[0061] In another embodiment the mode control data comprises address information addressing one or more cable modems to which said control data is directed, wherein said decoder and/or said receiver are to use said control data when the respective cable modem is addressed by said address information. For instance, a MAC ID, a Signal ID or a Stream ID may be used.

[0062] In still another embodiment the mode control data comprises data pattern information informing if and/or when data patterns contain data or not, wherein said decoder and/or said receiver are configured to use said data pattern information to switch between active mode and sleep mode. This allows frame based sleep mode. For instance, if no packet of the target data stream is in that frame, the sleep mode could be activated during this particular frame. This could be treated differently to the 'deep' sleep mode with the mode control data.

[0063] Fig. 14 illustrates another embodiment of a frame 700 of the present disclosure having a preamble 702 and a payload portion 704. The preamble 702 comprises a number of subsequently arranged LI blocks 703, which, in this embodiment, comprise identical (or almost identical) signaling data and have the same size in time and in frequency direction. The payload portion 704 comprises three data slices 705, 706, 707 each comprising one or more data patterns. In this embodiment the carrier spacing is adjusted to 12.5kHz and the channel bandwidths are multiples of 24MHz. The data slices 705, 706, 707are aligned to the LI blocks 703 in this embodiment.

[0064] Fig. 15 illustrates another embodiment of a frame 800 of the present disclosure having a preamble 802 and a payload portion 804. The preamble 802 comprises a number of subsequently arranged LI blocks 803. The payload portion 804 comprises three data slices 805, 806, 807 each comprising one or more data patterns. In this embodiment the carrier spacing is adjusted to 12.5kHz, too. But no fixed channel raster is generally required. Further, the data slices 805, 806, 807 are not aligned to the LI blocks 803 in this embodiment, but the channels (data slices) can be freely positioned at any frequency position.

[0065] As explained above, the receiver can freely and flexibly tune to the respectively wanted frequency position, such as the part 38 shown in Fig. 4. However, in order to be able to properly evaluate the signaling data of the signaling patterns 31 in case that the tuning position of the receiver does not match with the signaling pattern structure, the received signaling signals have to be re-ordered as schematically illustrated in Fig. 5 which shows this reordering in a schematic example. The last part 3 of a previous signaling pattern is received before the first part 31 " of a succeeding signaling pattern, where after the part 31 ' is placed after the part 31 " in order to reconstruct the original sequence of the signaling data, i.e. a complete and correctly ordered signaling pattern 40. This is particularly possible if the content of each signaling pattern 31 is the same.

[0066] It shall be noted that it is generally also possible that the preamble does not comprise an integer number of signaling patterns, but a non-integer number, e.g. 1.5 signaling patterns, in order to fill up the available transmission bandwidth. As long as the reception bandwidth of the receiver is equal to or larger than the bandwidth of one complete signaling pattern, the signaling data can be reconstructed as explained above with reference to Fig. 16. [0067] The advantages of the proposed device, system and method are that complex data stream scheduling to keep latency low (frame specific scheduler requires one frame buffering) is avoided. Further, a constant modulation and coding within one channel (= data slice with bandwidth of e.g. 24, 48, 192MHz) is possible, i.e. each data slice is operated in broadcast mode. The modulation and coding settings can be different for different data slices (i.e. data slice specific ,bit loading' only). There is no fine-granular bit loading within one channel, as the amplitude slope within one data slice is not significant. Amplitude differences within one data slice are averaged by frequency interleaving. Several data slices can be combined to one overall broad data stream, sharing the same preamble. The maximum bandwidth of a proposed frame is flexible and solely dependent on the CMTS capabilities.

[0068] Typically a CM decodes only one data slice, huge data pipes are realized by DOCSIS channel bonding. Preamble signal spectrum partitioning and data slice specific operation parameters can be provided. The Absolute OFDM concept is preferably used for unique signal signature across all current and future frequencies.

[0069] This provides a unique definition provided across the HFC spectrum, a reliable synchronization and offset compensation, a physical layer signaling of channels, allows for fast acquisition and avoids the need for blind scans or initial TS parsing. Further, with the proposed frame structure, generally no guard bands are required between data slices which leads to an increased efficiency.

[0070] According to the proposed frame structure the preamble preferably consists of repeated LI blocks in frequency direction. Preferably, an LI block has mixed pilots and data carriers and contains phy parameters of the following payload part. A single preamble symbol has typically enough signaling capacity thus requiring only a low overhead. A pilot sequence is preferably defined for the whole frequency range, starting from OHz, i.e. the concept of Absolute OFDM is preferably applied providing for an easy synchronization and offset compensation.

[0071] Generally, not every frame needs to include data for every cable modem. Signaling data are provided in the signaling pattern(s) if there are data for a specific cable modem in the following frame.

[0072] In an embodiment there is a single PLP (Physical Layer Pipe) or multiple PLPs (with the same parameters) per data slice, which provides a simple configuration and requires single ModCod settings. In another embodiment multiple PLPs are provided per data slice requiring PLP specific ModCod settings (i.e. specific QAM (Qaudrature Amplitude Modulation) constellation sizes and/or LDPC (Low-density parity-check) code rates), packet recognition, but enables that only packets from target PLP are decoded thus enabling large power savings. This allows different robustness levels for different frequencies, e.g. makes it possible to handle frequency slopes in higher frequencies. However, a tradeoff is to be made between required granularity vs. signaling overhead.

[0073] Fig. 17 is a hardware diagram of a processing system embodying aspects of this disclosure, including aspects involving a computer utilized to perform the steps of the proposed methods. The processes, algorithms and electronically driven systems described herein can be implemented via a discrete control device or computing system consistent with the structure shown in Fig. 17. Such a system is described herein as a processing system. Such a processing system or parts thereof can be used in a proposed cable modem and/or cable modem termination system.

[0074] As shown in Fig. 17, a processing system in accordance with this disclosure can be implemented using a microprocessor or its equivalent, such as a central processing unit (CPU) or at least one application specific processor ASP (not shown). The microprocessor utilizes a computer readable storage medium, such as a memory (e.g., ROM, EPROM, EEPROM, flash memory, static memory, DRAM, SDRAM, and their equivalents), configured to control the microprocessor to perform and/or control the processes and systems of this disclosure. Other storage mediums can be controlled via a controller, such as a disk controller, which can controls a hard disk drive or optical disk drive.

[0075] The microprocessor or aspects thereof, in an alternate embodiment, can include or exclusively include a logic device for augmenting or fully implementing this disclosure. Such a logic device includes, but is not limited to, an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA), a generic-array of logic (GAL), and their equivalents. The microprocessor can be a separate device or a single processing mechanism. Further, this disclosure can benefit from parallel processing capabilities of a multi-cored CPU.

[0076] In another aspect, results of processing or the input of data in accordance with this disclosure can be displayed via a display controller to a monitor. The display controller would then preferably include at least one graphic processing unit for improved computational efficiency. Additionally, an I/O (input/output) interface is provided for inputting data from a keyboard or a pointing device (not shown) for controlling parameters of the various processes and algorithms of this disclosure can be connected to the I/O interface to provide additional functionality and configuration options, or control display characteristics. Moreover, the monitor can be provided with a touch-sensitive interface to a command/instruction interface, and other peripherals can be incorporated, including a scanner or a web cam when image-based data entry is used. [0077] The above-noted components can be coupled to a network, as shown in Fig. 17, such as the Internet or a local intranet, via a network interface for the transmission or reception of data, including controllable parameters. The network provides a communication path to the mobile device, which can be provided by way of packets of data. Additionally, a central BUS is provided to connect the above hardware components together and provides at least one path for digital communication there between.

[0078] Obviously, numerous modifications and variations of the present disclosure are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the disclosure may be practiced otherwise than as specifically described herein.

[0079] In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality. A single element or other unit may fulfill the functions of several items recited in the claims. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.

[0080] In so far as embodiments of the disclosure have been described as being implemented, at least in part, by software-controlled data processing apparatus, it will be appreciated that a non-transitory machine-readable medium carrying such software, such as an optical disk, a magnetic disk, semiconductor memory or the like, is also considered to represent an embodiment of the present disclosure. Further, such a software may also be distributed in other forms, such as via the Internet or other wired or wireless telecommunication systems.

[0081] Any reference signs in the claims should not be construed as limiting the scope.

[0082] It follows a list of further preferred embodiments of the disclosed subject matter.

1. A cable modem for receiving signals transmitted within a transmission bandwidth by a cable modem termination system in a broadband communication system on the basis of a frame structure, said cable modem comprising:

a receiver that receives receive signals from said cable modem termination system;

wherein said receive signals are provided in frames of said frame structure, a frame comprising one or more signaling patterns and one or more data patterns following the one or more signaling patterns in the time direction, wherein the one or more data patterns in a frame are respectively followed by further data patterns succeeding the one or more data patterns in the time direction, wherein signaling data including mode control data are arranged in each of said one or more signaling patterns in a frame and wherein data are arranged in said one or more data patterns and said further data patterns in a frame,

2. The cable modem as defined in embodiment 1 ,

wherein said receiver is configured to maintain the reception bandwidth when the decoder switches from active mode into sleep mode.

3. The cable modem as defined in embodiment 1 ,

wherein said receiver is configured to switch between active mode and sleep mode based on the decoded mode control data.

4. The cable modem as defined in embodiment 3,

wherein said receiver is configured to reduce, when switching from active mode into sleep mode, the reception bandwidth to substantially cover the bandwidth of a single signaling pattern.

5. The cable modem as defined in embodiment 1,

wherein a frame comprises more than one signaling pattern adjacent to each other in the frequency direction, said at least two signaling patterns comprising substantially the same signaling data.

6. A cable modem for receiving signals transmitted within a transmission bandwidth by a cable modem termination system in a broadband communication system on the basis of a frame structure, said cable modem comprising:

a receiver that receives receive signals from said cable modem termination system; wherein said receive signals are provided in frames of said frame structure, a frame comprising more than one signaling pattern adjacent to each other in the frequency direction and one or more data patterns following the at least two signaling patterns in the time direction, wherein the one or more data patterns in a frame are respectively followed by further data patterns succeeding the one or more data patterns in the time direction, wherein signaling data including mode control data are arranged in each of said more than one signaling pattern in a frame and wherein data are arranged in said one or more data patterns and said further data patterns in a frame,

a decoder that is configured to decode said mode control data,

wherein said receiver is configured to switch between active mode and sleep mode based on the decoded mode control data and to reduce, when switching from active mode into sleep mode, the reception bandwidth to substantially cover the bandwidth of a single signaling pattern.

7. The cable modem as defined in embodiment 4 or 6,

wherein said receiver is configured to change, when switching from sleep mode into active mode, the reception bandwidth to the previous reception bandwidth used before switching from active mode into sleep mode or to a reception bandwidth defined in a decoded signaling pattern.

8. The cable modem as defined in embodiment 3 or 6,

wherein said receiver is configured to maintain the tuning frequency when switching from active mode into sleep mode.

9. The cable modem as defined in embodiment 3 or 6,

wherein said receiver is configured to change, when switching from active mode into sleep mode, the tuning frequency to a predetermined tuning frequency or a tuning frequency signaled in a decoded signaling pattern.

10. The cable modem as defined in embodiment 9, wherein said receiver is configured to change, when switching from active mode into sleep mode, the tuning frequency to the center frequency of said tuning bandwidth.

11. The cable modem as defined in embodiment 9,

wherein additional signaling data are arranged in one or more data patterns covered by the reception bandwidth at said predetermined tuning frequency in a frame and wherein said decoder is configured to decode, in the sleep mode, said one or more data patterns comprising said additional signaling data in addition to said signaling pattern.

12. The cable modem as defined in embodiment 9,

wherein said receiver is configured to change, when switching from sleep mode into active mode, the tuning frequency to the previous tuning frequency used before switching from active mode into sleep mode or to a tuning frequency defined in a decoded signaling pattern.

13. The cable modem as defined in embodiment 1 or 6,

wherein said decoder is configured to switch from sleep mode into active mode at least one frame before data arranged in said one or more data patterns and said further data patterns are to be decoded.

14. The cable modem as defined in embodiment 1 or 6,

wherein said mode control data comprises a mode trigger, mode flag or switching time indicator indicating the time of switching between active mode and sleep mode, wherein said decoder and/or said receiver are configured to use said mode trigger, mode flag or switching time indicator to actively switch themselves to the mode signaled by said mode trigger, mode flag or switching time indicator.

15. The cable modem as defined in embodiment 1 or 6,

wherein said mode control data comprises address information addressing one or more cable modems to which said control data is directed, wherein said decoder and/or said receiver are to use said control data when the respective cable modem is addressed by said address information. 16. The cable modem as defined in embodiment 1 or 6,

wherein said mode control data comprises data pattern information informing if and/or when data patterns contain data or not, wherein said decoder and/or said receiver are configured to use said data pattern information to switch between active mode and sleep mode.

17. The cable modem as defined in embodiment 1 or 6,

wherein said cable modem complies with a DOCSIS standard or EPOC operating system requirements.

18. A method for receiving signals transmitted within a transmission bandwidth by a cable modem termination system in a broadband communication system on the basis of a frame structure, said method comprising:

receiving receive signals from said cable modem termination system,

wherein said receive signals are provided in frames of said frame structure, a frame comprising one or more signaling patterns and one or more data patterns following the one or more signaling patterns in the time direction, wherein the one or more data patterns in a frame are respectively followed by further data patterns succeeding the one or more data patterns in the time direction, wherein signaling data including mode control data are arranged in each of said one or more signaling patterns in a frame and wherein data are arranged in said one or more data patterns and said further data patterns in a frame,;

tuning to and receiving a reception bandwidth covering the complete transmission bandwidth or a selected part of said transmission bandwidth, wherein said reception bandwidth covers at least one data pattern to be received;

decoding said mode control data;

switching between active mode and sleep mode based on the decoded mode control data; and

decoding, in the active mode, a signaling pattern and at least one data pattern covered by said reception bandwidth, and decoding, in the sleep mode, only a signaling pattern covered by said reception bandwidth. 19. A method for receiving signals transmitted within a transmission bandwidth by a cable modem termination system in a broadband communication system on the basis of a frame structure, said method comprising:

receiving receive signals from said cable modem termination system,

wherein said receive signals are provided in frames of said frame structure, a frame comprising more than one signaling pattern adjacent to each other in the frequency direction and one or more data patterns following the more than one signaling pattern in the time direction, wherein the one or more data patterns in a frame are respectively followed by further data patterns succeeding the one or more data patterns in the time direction, wherein signaling data including mode control data are arranged in each of said more than one signaling pattern in a frame and wherein data are arranged in said one or more data patterns and said further data patterns in a frame;

decoding said mode control data;

reducing, when switching from active mode into sleep mode, the reception bandwidth to substantially cover the bandwidth of a single signaling pattern.

20. A cable modem termination system for transmitting signals within a transmission bandwidth for reception by a cable modem in a broadband communication system on the basis of a frame structure, said cable modem termination system comprising:

a transmitter that transmits transmit signals to one or more cable modems.

21. The cable modem termination system as defined in embodiment 20,

wherein said mode control data is configured for being decoded by a cable modem and to cause said cable modem to switch between active mode and sleep mode based on the decoded mode control data and to reduce, when switching from active mode into sleep mode, the reception bandwidth to substantially cover the bandwidth of a single signaling pattern.

22. A cable modem termination system for transmitting signals within a transmission bandwidth for reception by a cable modem in a broadband communication system on the basis of a frame structure, said cable modem termination system comprising:

wherein said mode control data is configured for being decoded by a cable modem and to cause said cable modem to switch between active mode and sleep mode based on the decoded mode control data and to reduce, when switching from active mode into sleep mode, the reception bandwidth to substantially cover the bandwidth of a single signaling pattern; and

a transmitter that transmits transmit signals to one or more cable modems.

23. The cable modem termination system as defined in embodiment 20 or 22,

wherein said frame former is configured to arrange additional signaling data in one or more data patterns. 24. The cable modem termination system as defined in embodiment 20 or 22, wherein said frame former is configured to arrange a mode trigger, mode flag or switching time indicator indicating the time of switching between active mode and sleep mode in said mode control data for use by cable modem for to actively switch itself to the mode signaled by said mode trigger, mode flag or switching time indicator.

25. The cable modem termination system as defined in embodiment 20 or 22,

wherein said frame former is configured to arrange address information addressing one or more cable modems to which said control data is directed in said mode control data for use by said one or more cable modems when the respective cable modem is addressed by said address information.

26. The cable modem termination system as defined in embodiment 20 or 22,

wherein said frame former is configured to arrange data pattern information informing if and/or when data patterns contain data or not in said mode control data for use by a cable modem to switch between active mode and sleep mode.

27. The cable modem termination system as defined in embodiment 20 or 22,

wherein said cable modem termination system complies with a DOCSIS standard or EPOC operating system requirements.

28. A method for transmitting signals within a transmission bandwidth for reception by a cable modem in a broadband communication system on the basis of a frame structure, said method comprising:

a forming frames of said frame structure, a frame comprising one or more signaling patterns and one or more data patterns following the one or more signaling patterns in the time direction, wherein the one or more data patterns in a frame are respectively followed by further data patterns succeeding the one or more data patterns in the time direction, wherein signaling data including mode control data are arranged in each of said one or more signaling patterns in a frame and wherein data are arranged in said one or more data patterns and said further data patterns in a frame, wherein said mode control data is configured for being decoded by a cable modem and to cause said cable modem to switch between active mode and sleep mode based on the decoded mode control data, to decode, in the active mode, a signaling pattern and at least one data pattern covered by a reception bandwidth, and to decode, in the sleep mode, only a signaling pattern covered by said reception bandwidth; and

transmitting transmit signals to one or more cable modems.

29. A method for transmitting signals within a transmission bandwidth for reception by a cable modem in a broadband communication system on the basis of a frame structure, said method comprising:

forming frames of said frame structure, a frame comprising more than one signaling pattern adjacent to each other in the frequency direction and one or more data patterns following the more than one signaling pattern in the time direction, wherein the one or more data patterns in a frame are respectively followed by further data patterns succeeding the one or more data patterns in the time direction, wherein signaling data including mode control data are arranged in each of said more than one signaling pattern in a frame and wherein data are arranged in said one or more data patterns and said further data patterns in a frame,

transmitting transmit signals to one or more cable modems.

30. A computer program comprising program code means for causing a computer to perform the steps of said method as defined in embodiment 18, 19, 28 or 29 when said computer program is carried out on a computer.

31. A non-transitory computer-readable recording medium that stores therein a computer program product, which, when executed by a processor, causes the method according to embodiment 18, 19, 28 or 29 to be performed. 32. A broadband communication system comprising:

one or more cable modem termination systems as defined in embodiment 20 for transmitting signals within a transmission bandwidth for reception by a cable modem in a broadband communication system on the basis of a frame structure; and

one or more cable modems as defined in embodiment 1 for receiving signals transmitted within said transmission bandwidth by a cable modem termination system.

33. A broadband communication system comprising:

one or more cable modem termination systems as defined in embodiment 22 for transmitting signals within a transmission bandwidth for reception by a cable modem in a broadband communication system on the basis of a frame structure; and

one or more cable modems as defined in embodiment 6 for receiving signals transmitted within said transmission bandwidth by a cable modem termination system.

Claims

2. The cable modem as claimed in claim 1,

3. The cable modem as claimed in claim 1 ,

4. A cable modem for receiving signals transmitted within a transmission bandwidth by a cable modem termination system in a broadband communication system on the basis of a frame structure, said cable modem comprising:

wherein said receive signals are provided in frames of said frame structure, a frame comprising more than one signaling pattern adjacent to each other in the frequency direction and one or more data patterns following the at least two signaling patterns in the time direction, wherein the one or more data patterns in a frame are respectively followed by further data patterns succeeding the one or more data patterns in the time direction, wherein signaling data including mode control data are arranged in each of said more than one signaling pattern in a frame and wherein data are arranged in said one or more data patterns and said further data patterns in a frame,

a decoder that is configured to decode said mode control data,

5. The cable modem as claimed in claim 3 or 4,

6. The cable modem as claimed in claim 3 or 4,

7. The cable modem as claimed in claim 1 or 4, wherein said decoder is configured to switch from sleep mode into active mode at least one frame before data arranged in said one or more data patterns and said further data patterns are to be decoded.

8. The cable modem as claimed in claim 1 or 4,

9. The cable modem as claimed in claim 1 or 4,

wherein said mode control data comprises address information addressing one or more cable modems to which said control data is directed, wherein said decoder and/or said receiver are to use said control data when the respective cable modem is addressed by said address information.

10. The cable modem as claimed in claim 1 or 4,

11. A method for receiving signals transmitted within a transmission bandwidth by a cable modem termination system in a broadband communication system on the basis of a frame structure, said method comprising:

receiving receive signals from said cable modem termination system,

decoding said mode control data;

decoding, in the active mode, a signaling pattern and at least one data pattern covered by said reception bandwidth, and decoding, in the sleep mode, only a signaling pattern covered by said reception bandwidth.

12. A method for receiving signals transmitted within a transmission bandwidth by a cable modem termination system in a broadband communication system on the basis of a frame structure, said method comprising:

receiving receive signals from said cable modem termination system,

decoding said mode control data;

13. A cable modem termination system for transmitting signals within a transmission bandwidth for reception by a cable modem in a broadband communication system on the basis of a frame structure, said cable modem termination system comprising:

a transmitter that transmits transmit signals to one or more cable modems.

14. A cable modem termination system for transmitting signals within a transmission bandwidth for reception by a cable modem in a broadband communication system on the basis of a frame structure, said cable modem termination system comprising:

15. A method for transmitting signals within a transmission bandwidth for reception by a cable modem in a broadband communication system on the basis of a frame structure, said method comprising:

a forming frames of said frame structure, a frame comprising one or more signaling patterns and one or more data patterns following the one or more signaling patterns in the time direction, wherein the one or more data patterns in a frame are respectively followed by further data patterns succeeding the one or more data patterns in the time direction, wherein signaling data including mode control data are arranged in each of said one or more signaling patterns in a frame and wherein data are arranged in said one or more data patterns and said further data patterns in a frame,

transmitting transmit signals to one or more cable modems.

16. A method for transmitting signals within a transmission bandwidth for reception by a cable modem in a broadband communication system on the basis of a frame structure, said method comprising:

transmitting transmit signals to one or more cable modems.

17. A computer program comprising program code means for causing a computer to perform the steps of said method as claimed in claim 1 1 , 12, 15 or 16 when said computer program is carried out on a computer.

18. A non-transitory computer-readable recording medium that stores therein a computer program product, which, when executed by a processor, causes the method according to claim 1 1 , 12, 15 or 16 to be performed.

19. A broadband communication system comprising:

one or more cable modem termination systems as claimed in claim 13 for transmitting signals within a transmission bandwidth for reception by a cable modem in a broadband communication system on the basis of a frame structure; and

one or more cable modems as claimed in claim 1 for receiving signals transmitted within said transmission bandwidth by a cable modem termination system.

20. A broadband communication system comprising:

one or more cable modem termination systems as claimed in claim 14 for transmitting signals within a transmission bandwidth for reception by a cable modem in a broadband communication system on the basis of a frame structure; and

one or more cable modems as claimed in claim 4 for receiving signals transmitted within said transmission bandwidth by a cable modem termination system.