SIST EN 300 175-2 V1.5.1:2003

SLOVENSKI STANDARD
01-december-2003
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Digital Enhanced Cordless Telecommunications (DECT); Common Interface (CI); Part 2:
Physical Layer (PHL)
Ta slovenski standard je istoveten z: EN 300 175-2 Version 1.5.1
ICS:
33.070.30 'LJLWDOQHL]EROMãDQH Digital Enhanced Cordless
EUH]YUYLþQHWHOHNRPXQLNDFLMH Telecommunications (DECT)
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2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

European Standard (Telecommunications series)
Digital Enhanced Cordless Telecommunications (DECT);
Common Interface (CI);
Part 2: Physical Layer (PHL)
2 ETSI EN 300 175-2 V1.5.1 (2001-02)
Reference
REN/DECT-000157-2
Keywords
DECT, radio
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ETSI
3 ETSI EN 300 175-2 V1.5.1 (2001-02)
Contents
Intellectual Property Rights .6
Foreword.6
1 Scope.7
2 References.7
3 Definitions and abbreviations.8
3.1 Definitions . 8
3.2 Abbreviations. 9
4 PHL services .10
4.1 RF channels (access in frequency) . 10
4.1.1 Nominal position of RF carriers. 10
4.1.2 Accuracy and stability of RF carriers. 11
4.2 Time Division Multiple Access (TDMA) structure (access in time). 11
4.2.1 Frame, full-slot, double-slot, and half-slot structure . 11
4.2.2 Reference timer accuracy and stability. 12
4.2.3 RFP transmission jitter. 12
4.2.4 PP reference timer synchronization. 13
4.2.5 System synchronization. 13
4.2.6 Inter-system synchronization. 13
4.2.7 Reference timer adjustment for synchronization. 13
4.3 Cells (access in space) . 13
4.4 Physical packets . 14
4.4.1 The short physical packet P00 . 14
4.4.2 The basic physical packet P32. 15
4.4.3 The low capacity physical packet P08j. 15
4.4.4 The high capacity physical packet P80. 16
4.5 Physical channels . 16
4.5.1 Ra (K,L,M,N) notation. 16
4.5.2 The short physical channel R00(K,L,M,N) . 17
4.5.3 The basic physical channel R32(K,L,M,N) . 17
4.5.4 The low-rate physical channel R08j(K,L,M,N) . 18
4.5.5 The high capacity physical channel R80(K,L,M,N). 19
4.6 Synchronization field S. 19
4.7 D-field . 20
4.7.1 Physical packet P00 . 20
4.7.2 Physical packet P32 . 20
4.7.3 Physical packet P08j . 20
4.7.4 Physical packet P80 . 20
4.8 Z-field. 21
4.9 Bit pattern during ramping. 21
5 Transmission of physical packets .21
5.1 Definitions . 21
5.1.1 End of the physical packet. 21
5.1.2 Transmitted power . 21
5.1.3 Normal Transmitted Power (NTP). 22
5.2 Transmission burst . 22
5.2.1 Transmitter attack time. 22
5.2.2 Transmitter release time. 22
5.2.3 Minimum power . 22
5.2.4 Maximum power. 22
5.2.5 Maintenance of transmission after packet end. 22
5.2.6 Transmitter idle power output. 23
5.3 Transmitted power. 23
5.3.1 Peak power per transceiver. 23
ETSI
4 ETSI EN 300 175-2 V1.5.1 (2001-02)
5.3.1.1 PP and RFP with an integral antenna. 23
5.3.1.2 PP and RFP with external connections for all antennas. 23
5.3.2 Maximum EIRP and number of transceivers.23
5.4 RF carrier modulation. 23
5.4.1 Modulation method. 23
5.4.2 Definition of "1" and "0". 24
5.4.3 Deviation limits . 24
5.5 Unwanted RF power radiation . 24
5.5.1 Emissions due to modulation. 24
5.5.2 Emissions due to transmitter transients . 25
5.5.3 Emissions due to intermodulation. 25
5.5.4 Spurious emissions when allocated a transmit channel. 25
6 Reception of physical packets .26
6.1 Definitions and conditions for clause 6 . 26
6.1.1 Power levels and field strength. 26
6.1.2 Test conditions. 26
6.1.3 Reference DECT radio end point. 26
6.2 Radio receiver sensitivity. 27
6.3 Radio receiver reference bit error rate and frame error ratio. 27
6.4 Radio receiver interference performance. 27
6.5 Radio receiver blocking. 27
6.5.1 Owing to signals occurring at the same time but on other frequencies . 27
6.5.2 Owing to signals occurring at a different time. 28
6.6 Receiver intermodulation performance. 28
6.7 Spurious emissions when not allocated a transmit channel. 28
6.7.1 Out of band. 28
6.7.2 In the DECT band. 28
7 Primitives between physical layer and other entities .29
7.1 Medium access control layer (D-SAP) . 29
7.1.1 PL_TX {req} . 29
7.1.2 PL_RX {req,cfm} . 30
7.1.3 PL_FREQ_ADJ {req,}. 30
7.2 Management entity (PM-SAP). 30
7.2.1 PL_ME_SYNC {req,cfm}. 30
7.2.2 PL_ME_SIG_STR {req,cfm}. 30
7.2.3 PL_ME_TIME_ADJ {req,cfm}. 31
8 PHL procedures .31
8.1 Addition of synchronization field and transmission . 31
8.2 Packet reception and removal of synchronization field . 31
8.3 Measurement of signal strength . 32
8.4 Synchronization pulse detection. 32
8.5 Timing adjustment. 32
8.6 Frequency adjustment. 32
9 Management entity procedures related to PHL .32
9.1 List of quietest physical channels. 32
9.2 Physical channels with greatest field strength (PP only) . 33
9.3 Extract timing. 33
Annex A (normative): RF safety requirements.34
A.1 Recommendation.34
A.2 Safety distances .34
Annex B (normative): Synchronization port .35
B.1 General requirements.35
B.2 Wired synchronization ports .36
B.2.1 Synchronization signal . 37
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5 ETSI EN 300 175-2 V1.5.1 (2001-02)
B.3 GPS synchronization.38
B.3.1 Synchronization signal . 39
B.3.2 DECT timings derivation from the GPS time . 39
B.3.2.1 DECT multiframe number synchronization using GPS. 39
B.3.2.2 DECT PSCN synchronization using GPS . 40
B.4 Guidance for installation.40
B.4.1 Interconnection cable. 40
B.4.2 Propagation delay of synchronization signals. 40
B.4.2.1 Calculation of Propagation delay (informative). 40
B.4.2.2 Delay compensation. 41
B.4.3 GPS receiver stability.41
Annex C (normative): Prolonged preamble.42
C.1 Bit pattern.42
C.2 The power-time template .42
Annex D (normative): 4-level/8-level modulation option.43
D.1 The Π/2-DBPSK modulation scheme.44
D.1.1 RF carrier modulation. 44
D.1.1.1 Modulation accuracy. 44
D.1.2 Transmission of physical packets. 44
D.2 The Π/4-DQPSK modulation scheme.44
D.2.1 RF carrier modulation. 44
D.2.1.1 Modulation accuracy. 45
D.2.2 Transmission of physical packets. 45
D.3 The Π/8-D8PSK modulation scheme.45
D.3.1 RF carrier modulation. 45
D.3.1.1 Modulation accuracy. 46
D.3.2 Transmission of physical packets. 46
Annex E (normative): Power control procedures.47
E.1 Definitions of parameters and relations between parameters.48
E.2 Procedure for PP power adjustment due to movement .49
E.3 Setting the power control threshold, RSSpT.49
Annex F (informative): DECT carrier numbers and carrier positions in the range 1 880 MHz
to 1 938 MHz.51
Annex G (informative): Bibliography.52
History .53
ETSI
6 ETSI EN 300 175-2 V1.5.1 (2001-02)
Intellectual Property Rights
IPRs essential or potentially essential to the present document may have been declared to ETSI. The information
pertaining to these essential IPRs, if any, is publicly available for ETSI members and non-members, and can be found
in ETSI SR 000 314: "Intellectual Property Rights (IPRs); Essential, or potentially Essential, IPRs notified to ETSI in
respect of ETSI standards", which is available from the ETSI Secretariat. Latest updates are available on the ETSI Web
server (http://www.etsi.org/ipr).
Pursuant to the ETSI IPR Policy, no investigation, including IPR searches, has been carried out by ETSI. No guarantee
can be given as to the existence of other IPRs not referenced in ETSI SR 000 314 (or the updates on the ETSI Web
server) which are, or may be, or may become, essential to the present document.
Foreword
This European Standard (Telecommunications series) has been produced by ETSI Project Digital Enhanced Cordless
Telecommunications (DECT).
The present document is part 2 of a multi-part EN covering the Common Interface (CI) for the Digital Enhanced
Cordless Telecommunications (DECT), as identified below:
Part 1: "Overview";
Part 2: "Physical Layer (PHL)";
Part 3: "Medium Access Control (MAC) layer";
Part 4: "Data Link Control (DLC) layer";
Part 5: "Network (NWK) layer";
Part 6: "Identities and addressing";
Part 7: "Security features";
Part 8: "Speech coding and transmission".
Further details of the DECT system may be found in TR 101 178 [10] and ETR 043 [9].
National transposition dates
Date of adoption of this EN: 16 February 2001
Date of latest announcement of this EN (doa): 31 May 2001
Date of latest publication of new National Standard
or endorsement of this EN (dop/e): 30 November 2001
Date of withdrawal of any conflicting National Standard (dow): 30 November 2001
ETSI
7 ETSI EN 300 175-2 V1.5.1 (2001-02)
1 Scope
The present document gives an introduction and overview of the complete Digital Enhanced Cordless
Telecommunications (DECT) Common Interface (CI).
The present document of the DECT CI specifies the physical channel arrangements. DECT physical channels are radio
communication paths between two radio end points. A radio end point is either part of the fixed infrastructure or a
Portable Part (PP), typically a handset. The assignment of one or more particular physical channels to a call is the task
of higher layers.
The Physical Layer (PHL) interfaces with the Medium Access Control (MAC) layer, and with the Lower Layer
Management Entity (LLME). On the other side of the PHL is the radio transmission medium which has to be shared
extensively with other DECT users and a wide variety of other radio services. The tasks of the PHL can be grouped into
five categories:
a) to modulate and demodulate radio carriers with a bit stream of a defined rate to create a radio frequency channel;
b) to acquire and maintain bit and slot synchronization between transmitters and receivers;
c) to transmit or receive a defined number of bits at a requested time and on a particular frequency;
d) to add and remove the synchronization field and the Z-field used for rear end collision detection;
e) to observe the radio environment to report signal strengths.
2 References
The following documents contain provisions which, through reference in this text, constitute provisions of the present
document.
• References are either specific (identified by date of publication, edition number, version number, etc.) or
non-specific.
• For a specific reference, subsequent revisions do not apply.
• For a non-specific reference, the latest version applies.
[1] ETSI EN 300 175-1: "Digital Enhanced Cordless Telecommunications (DECT); Common
Interface (CI); Part 1: Overview".
[2] ETSI EN 300 175-3: "Digital Enhanced Cordless Telecommunications (DECT); Common
Interface (CI); Part 3: Medium Access Control (MAC) layer".
[3] ETSI EN 300 175-4: "Digital Enhanced Cordless Telecommunications (DECT); Common
Interface (CI); Part 4: Data Link Control (DLC) layer".
[4] ETSI EN 300 175-5: "Digital Enhanced Cordless Telecommunications (DECT); Common
Interface (CI); Part 5: Network (NWK) layer".
[5] ETSI EN 300 175-6: "Digital Enhanced Cordless Telecommunications (DECT); Common
Interface (CI); Part 6: Identities and addressing".
[6] ETSI EN 300 176-1: "Digital Enhanced Cordless Telecommunications (DECT); Approval test
specification; Part 1: Radio".
[7] ITU – R M.1457: "Detailed specifications of International Mobile Telecommunications-2000
(IMT-2000)".
[8] EIA TIA/EIA-422-B: "Electrical Characteristics of Balanced Voltage Digital Interface
Circuits R (2000)".
ETSI
8 ETSI EN 300 175-2 V1.5.1 (2001-02)
[9] ETSI ETR 043: "Digital Enhanced Cordless Telecommunications (DECT); Common Interface
(CI); Services and facilities requirements specification".
[10] ETSI TR 101 178: "Digital Enhanced Cordless Telecommunications (DECT); A High Level Guide
to the DECT Standardization".
3 Definitions and abbreviations
3.1 Definitions
For the purposes of the present document the following terms and definitions apply:
antenna diversity: see EN 300 175-1 [1]
cell: see EN 300 175-1 [1]
Central Control Fixed Part (CCFP): see EN 300 175-1 [1]
channel: see EN 300 175-1 [1]
cluster: see EN 300 175-1 [1]
Connection Oriented mode (C/O): see EN 300 175-1 [1]
Cordless Radio Fixed Part (CRFP): see EN 300 175-1 [1]
coverage area: see EN 300 175-1 [1]
Dect Network (DNW): see EN 300 175-1 [1]
double duplex bearer: see EN 300 175-1 [1]
double simplex bearer: see EN 300 175-1 [1]
double slot: see EN 300 175-1 [1]
down-link: see EN 300 175-1 [1]
duplex bearer: see EN 300 175-1 [1]
Fixed Part (DECT Fixed Part) (FP): see EN 300 175-1 [1]
Fixed Radio Termination (FT): see EN 300 175-1 [1]
frame: see EN 300 175-1 [1]
full slot (slot): see EN 300 175-1 [1]
guard space: see EN 300 175-1 [1]
half slot: see EN 300 175-1 [1]
handover: see EN 300 175-1 [1]
intercell handover: see EN 300 175-1 [1]
intracell handover: see EN 300 175-1 [1]
Lower Layer Management Entity (LLME): see EN 300 175-1 [1]
multiframe: see EN 300 175-1 [1]
physical channel (channel): see EN 300 175-1 [1]
Portable Part (DECT Portable Part) (PP): see EN 300 175-1 [1]
ETSI
9 ETSI EN 300 175-2 V1.5.1 (2001-02)
Portable radio Termination (PT): see EN 300 175-1 [1]
public access service: see EN 300 175-1 [1]
radio channel: see EN 300 175-1 [1]
radio end point: see EN 300 175-1 [1]
Radio Fixed Part (RFP): see EN 300 175-1 [1]
Repeater Part (REP): see EN 300 175-1 [1]
RF carrier (carrier): see EN 300 175-1 [1]
RF channel: see EN 300 175-1 [1]
simplex bearer: see EN 300 175-1 [1]
Single Radio Fixed Part (SRFP): see EN 300 175-1 [1]
TDMA frame: see EN 300 175-1 [1]
Wireless Relay Station (WRS): see EN 300 175-1 [1]
3.2 Abbreviations
For the purposes of the present document the following abbreviations apply:
ACP Adjacent Channel Power
ACK Acknowledgement
CCFP Central Control Fixed Part
CI Common Interface (standard)
CRFP Cordless Radio Fixed Part
dBc dB relative to the peak power of an unmodulated carrier
dBm dB relative to 1 milliwatt
DECT Digital Enhanced Cordless Telecommunications
DLC Data Link Control layer
EIRP Effective Isotropic Radiated Power
ERP Effective Radiated Power
FP Fixed Part
FT Fixed radio Termination
GFSK Gaussian Frequency Shift Keying
GMSK Gaussian Minimum Shift Keying
LLME Lower Layer Management Entity
MAC Medium Access Control layer
NTP Normal Transmitted Power
PHL Physical Layer
PHS Portable HandSet
PP Portable Part
ppm parts per million
PT Portable radio Termination
REP Repeater Part
RF Radio Frequency
RFP Radio Fixed Part
RSSI Radio Signal Strength Indicator
SAR Specific Absorption Rate
TDD Time Division Duplex
TDMA Time Division Multiple Access
WRS Wireless Relay Station
ETSI
10 ETSI EN 300 175-2 V1.5.1 (2001-02)
4PHLservices
A physical channel provides a simplex bit-pipe between two radio end points. To establish, for example, a duplex
telephone connection, two physical channels have to be established between the endpoints.
Radio spectrum is needed to create a physical channel. The radio spectrum space has three dimensions:
- geometric (geographic) space;
- frequency; and
- time.
Spectrum is assigned to physical channels by sharing it in these three dimensions.
DECT provides a mechanism called "handover", to release a physical channel and to establish another one in any or all
of the three dimensions without releasing the end to end connection.
The requirements of the present document should be read in conjunction with EN 300 176-1 [6].
The requirements specified apply for nominal conditions unless extreme conditions are stated. Tests at extreme
conditions may include combinations of limit values of extreme temperature and of power supply variation, defined for
each case in EN 300 176-1 [6].
Nominal and extreme temperature ranges are defined below:
Nominal temperature: PP, FP, RFP, CCFP +15 °C to +35 °C;
Extreme temperature: PP 0 °C to +40 °C;
FP, RFP, CCFP, class E1 +10 °C to +40 °C;
FP, RFP, CCFP, class E2 -10 °C to +55 °C.
The environmental class E1 refers to installation in indoor heated and/or cooled areas allowing for personal comfort,
e.g. homes, offices, laboratories or workshops. The environmental class E2 refers to all other installations.
For nominal temperature, each measurement is made at the temperature of the test site, which shall be within +15 °C to
+35 °C. For extreme temperatures, additional measurements are made, at each limit value of the extreme temperature.
4.1 RF channels (access in frequency)
4.1.1 Nominal position of RF carriers
Ten RF carriers shall be placed into the frequency band 1 880 - 1 900 MHz with centre frequencies Fc given by:
Fc = F0 - c x 1,728 MHz.
where: F0 = 1 897,344 MHz; and
c = 0,1, ., 9.
Above this band, additional carriers are defined with centre frequencies Fc given by:
Fc = F9 + c x 1,728 MHz;
and c ≥ 10 and RF band = 00001. (See EN 300 175-3 [2], clause 7.2.3.3.1).
Annex F shows the carrier frequencies for c = 0 to 9 and for c ≥ 10 and RF band = 00001.
ETSI
11 ETSI EN 300 175-2 V1.5.1 (2001-02)
The frequency band between Fc - 1,728/2 MHz and Fc + 1,728/2 MHz shall be designated RF channel c.
NOTE: A nominal DECT RF carrier is one whose centre frequency is generated by the formula:
Fg = F0 - g x 1,728 MHz, where g is any integer.
All DECT equipment should when allowed be capable of working on all 10 RF channels, c= 0,1, ., 9.
New or modified carrier positions and/or frequency bands can (locally) be defined when needed by utilizing reserved
RF bands, e.g. for emerging DECT applications in the UMTS/IMT-2000 bands [7].
4.1.2 Accuracy and stability of RF carriers
At an RFP the transmitted RF carrier frequency corresponding to RF channel c shall be in the range Fc ± 50 kHz at
extreme conditions.
At a PP the centre frequency accuracy shall be within ± 50 kHz at extreme conditions either relative to an absolute
frequency reference or relative to the received carrier, except that during the first 1 s after the transition from the idle-
locked state to the active-locked state the centre frequency accuracy shall be within ± 100 kHz at extreme conditions
relative to the received carrier.
NOTE: The above state transition is defined in EN 300 175-3 [2].
The maximum rate of change of the centre frequency at both the RFP and the PP while transmitting, shall not exceed
15 kHz per slot.
4.2 Time Division Multiple Access (TDMA) structure (access in
time)
4.2.1 Frame, full-slot, double-slot, and half-slot structure
To access the medium in time, a regular TDMA structure is used. The structure repeats in frames of 11 520 symbols,
and the data is transmitted at a symbol rate of 1 152 ksymbol/s. Within this frame 24 full-slots are created, each
consisting of two half-slots. A double slot has a length of two full slots, and starts concurrently with an even numbered
full slot (see figures 1, 2 and 3).
NOTE: Some DECT documents sometimes refer to bits instead of symbols due to the fact that symbol and bit
become synonyms for the mandatory 2-level modulation, for which most physical layer tests are defined,
see EN 300 176-1 [6].
normal normal
RFP transmit PP transmit
full full full full full full full full full
slot slot slot slot slot slot slot slot slot
23 0 1 2 11 12 13 23 0
one frame, 11 520 bits
Figure 1: Full slot format
Full-slots are numbered from K = 0 to 23, and half-slots are numbered L = 0 or 1, where half-slot 0 occurs earlier than
half-slot 1. Normally full-slots K = 0 to 11 are used in the RFP to PP direction, while full slots K = 12 to 23 are
normally used in the PP to RFP direction. Double slots are numbered K = 0 to 22 for even values of K.
Each full-slot has a duration of 480 symbol intervals. Symbol intervals within a full-slot are denoted f0 to f479 where
interval f0 occurs earlier than interval f1. Each half-slot has a duration of 240 symbol intervals. Half-slots commence at
f0 or f240 (see figure 2).
ETSI
12 ETSI EN 300 175-2 V1.5.1 (2001-02)
480 bits
full-slot (K-1) full-slot (K) full-slot (K+1)
half-slot half-slot half-slot half-slot
L=1 L=0 L=1 L=0
240 bits 240 bits
f0
f240 f479
Figure 2: Half-slot format
Each double slot has a duration of 960 symbol intervals. Symbol intervals within a double slot are denoted f0 to f959.
Symbols f0 to f479 coincide with the same notation for full slots with even K, K(e).
960 bits
double-slot (K(e)-2) double-slot (K(e)) double-slot (K(e)+2)
full-slot full-slot full-slot full-slot
K(e)-1 K(e) K(e)+1 K(e)+2
480 bits 480 bits
f0 f479
f959
Figure 3: Double slot format
NOTE: Each radio end point has its own timing of the TDMA structure due to propagation delay and non-
synchronized systems.
4.2.2 Reference timer accuracy and stability
The reference timer of a RFP or a PP is a notional clock to which the timing parameters of the TDMA framing are
related.
A PP shall have its reference timer stability and accuracy better than 25 ppm at extreme conditions.
RFPs that can work with more than one duplex pair of physical channels per frame are known as multi-channel RFPs.
Single channel RFPs can only work with one duplex pair of physical channels per frame (excluding handover
situations).
A multi channel RFP shall have its reference timer stability and accuracy better than 5 ppm and better than 10 ppm at
extreme conditions.
A single channel RFP shall have reference timer stability and accuracy better than 10 ppm at extreme conditions.
4.2.3 RFP transmission jitter
The nominal time when a packet should occur at the RFP antenna is (by this definition) synchronous to the RFP
reference timer.
The jitter of a RFP packet transmission in a slot refers to the occurrence at the antenna of the start of symbol p0 of that
packet. The jitter is defined in relation to the reference timer of that RFP.
The jitter of a packet transmission shall be less than ± 1µs at extreme conditions.
The jitter between p0 and every other symbol in a packet shall be within ± 0,1µs.
NOTE: 0,1µs corresponds to 250 ppm.
ETSI
13 ETSI EN 300 175-2 V1.5.1 (2001-02)
4.2.4 PP reference timer synchronization
A PP shall take its reference timer parameters, including half-slot, full-slot, frame, multi-frame and receiver scan (see
synchronization, EN 300 175-3 [2]) from any channel of any of the RFPs that it is locked to.
It is allowed (but not required) to have more than one PP reference timer.
The reference timer used for a PP transmission to a RFP shall be synchronized to packets (see clause 4.4) received from
that RFP or from a RFP to which handover (see clause 4.2.5) is allowed.
This reference timer for packet transmission timing is nominally (by this definition) synchronized to the time when the
last packet used for synchronization occurred at the PP antenna.
When a PP transmits a packet, the start of transmission of symbol p0 of the packet shall occur at the PP antenna ± 2µs
at extreme conditions from the nominal transmission time as given by an ideal PP reference timer with 0 ppm accuracy.
An exception is allowed for a dummy bearer change request packet transmission (see EN 300 175-3 [2], clause 7.2.5.6),
when the nominal transmission time shall be given by the actual PP reference timer.
NOTE: The reason for the exception is that a residential PP may need to send the dummy bearer change request
after a sudden slot theft in the idle locked mode. In this case the last synchronization of the reference
timer can be more than 16 frame old. For all other packet transmissions, including bearer set up, the
synchronization is normally less than one frame old.
The jitter between p0 and every other symbol in a packet shall be within ± 0,1µs.
Connections to different RFPs are allowed (but not required) to have different reference timers.
4.2.5 System synchronization
RFPs on the same FP shall be in half-slot, full-slot and frame synchronism. If internal handover is provided (see
EN 300 175-3 [2] and EN 300 175-4 [3]), receiver scan and multiframe synchronism is also required.
The difference between reference timers of RFPs of the same FP shall be less than 4µs if internal handover is provided
between these RFPs.
NOTE: Related to its reference timer, the PP or RFP synchronization window (see EN 300 175-3 [2]) should be at
least ± 14 symbols, when expecting a first reception and if intracell handover is provided, else ± 4
symbols.
4.2.6 Inter-system synchronization
Synchronization between FPs can be provided via an optional synchronization port (see annex B).
NOTE: RFPs of synchronized FPs should have geographically unique Fixed Part MAC Identities (FMIDs)
(see EN 300 175-6 [5]).
4.2.7 Reference timer adjustment for synchronization
To obtain system and inter-system synchronization, a RFP or PP may alter the length of a single frame by any amount,
or, it may alter the length of successive frames by up to 2 symbols.
NOTE 1: Framelength alterations should be performed in accordance to the reference timer stability and accuracy
requirements for RFPs and PPs as specified in clause 4.2.2.
NOTE 2: If the timing of RFPs is adjusted outside the specification of clause 4.2.2 then PPs are not expected to
remain in the IDLE_LOCKED state. Therefore such timing adjustments should be made as infrequently
as possible by RFP reference timers.
4.3 Cells (access in space)
The third dimension to divide spectrum space is the geographical volume. Propagation losses may allow time-frequency
combinations to be reused in different places.
ETSI
14 ETSI EN 300 175-2 V1.5.1 (2001-02)
4.4 Physical packets
Data is transmitted within the frequency, time, and space dimensions using physical packets. Physical packets shall be
of one of the following types:
- short physical packet P00;
- basic physical packet P32;
- low capacity physical packet P08j;
- high capacity physical packet P80.
All RFPs shall be capable of transmitting, and all PPs shall be capable of receiving, short physical packets P00. All
radio end points shall be capable of transmitting and receiving at least one of the physical packet types P32, P08j, or
P80.
Each physical packet contains a synchronization field S and a data field D. The packets P80, P32 and P08j may contain
an optional collision detection field, Z.
4.4.1 The short physical packet P00
The short physical packet P00 consists of 96 data symbols, used for dummy bearers and short slot connectionless
bearers.
The data symbols are denoted p0 to p95 where p0 occurs earlier than p1. When the packet is transmitted, the beginning
of symbol p0 coincides with the beginning of symbol interval f0 of the full-slot being used (see figure 4).
full-slot K
f479
f0
p95
p0
packet P00
Figure 4: Short packet P00
ETSI
15 ETSI EN 300 175-2 V1.5.1 (2001-02)
4.4.2 The basic physical packet P32
The basic physical packet P32, used in the most common types of connection (e.g. telephony), consists of 420 or 424
data symbols.
The data symbols are denoted p0 to p423 where p0 occurs earlier than p1. When the packet is transmitted, the beginning
of symbol p0 coincides with the beginning of symbol interval f0 of the full-slot being used (see figure 5).
full-slot K
f479
f0
p0 p419 p423
packet P32
Figure 5: Basic packet P32
4.4.3 The low capacity physical packet P08j
The low capacity physical packet P08j consists of 180+j or
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