Section General Descriptions, Multi-band, Dcs

SECTION 2 GENERAL DESCRIPTIONS

2.1 Multi-band :

CMD-J16 support E-GSM 900 and DCS 1800 multi-band functionality.

For the use in Europe and in other countries worldwide, ETSI has specified GSM standards into two frequency bands. That is the 900-MHz and 1800-MHz band and is usually referred to as GSM900 and GSM1800 (formerly DCS1800).

While the 900-MHz band has 124 channels (extended version: 175), the 1800-MHz band with its 375 channels provides a three-times higher capacity. Not only as a result of this large range of channels but also due to the low transmission power and the transmission distance, GSM1800 supports a higher quantity of RF-channels.

The Dual band technology enables a network operator with spectrum at both 900MHz and 1800MHz to support the seamless use of dual band handsets across both frequencies. By supporting seamless handovers between 900MHz and 1800MHz, Dual band networks can provide major benefits in terms of capacity enhancement and revenue optimisation through the introduction of new services.

The CMD-J16 is a phase II, GSM 900 class 4, DCS 1800 class 1 mobile phone. The nominal maximum output power for GSM 900 is 2W, for DCS 1800 1W.

It supports the extra functionality required for multi-band mobile stations: Inter-band/”seamless” hand-over, channel assignment, cell selection and re-selection, all between both bands within a Public Land Mobile Network. The manual and automatic PLMN selection in both bands is given.

The user does not need any special action to use the multi-band functionality of the phone. Users are able to manually roam between PLMN’s operating in GSM 900 and DCS 1800 bands.

E-GSM

With the further development of the GSM standard, an additional range of frequencies has been made available to the “Global system for mobile communications”. For each of the two duplex frequency ranges, one for the forward direction and one for the reverse direction, additional 10 MHz have been added to the bottom end of the bands, extending the frequency range to 50 further channels.

The mobile station transmits in the 880- to 915 MHz range, and the base station transmits in the 925- to 960 MHz range. A duplex spacing of 45 MHz is used, the base station always transmits on the high side of the duplex frequency pair.

The numbering for these additional channels is from 974 to 1023. This is done to avoid assigning one channel number twice within the same standard.

Compared to the primary GSM system, Channel number 0 is used in the extended GSM system, since it does not make sense to reserve it at a guard band within the E-GSM bands. Now, the lowest channel, number 974 (880.0 MHz), serves as the guard band between GSM and other services on lower frequencies.

DCS 1800

DCS-1800 uses the frequency ranges of 1710 to 1785 MHz in the uplink direction, and 1805 to 1880 MHz in the downlink direction.

From these figures it follows that the duplex spacing is 95 MHz with 374 channels with bandwidths of 200 kHz each.

The channels are numbered from 512 to 885 in order to distinguish them from the channels in the primary and extended GSM frequency bands.

CMD-J16 specifications

The Sony CMD-J16, released in the late 1990s, exemplifies the innovative spirit of mobile communication technology during that era. This compact mobile phone showcased advanced features for its time, appealing to tech enthusiasts and casual users alike.

One of the standout characteristics of the CMD-J16 is its sleek design. Weighing in at just 113 grams and measuring 135 x 52 x 21 mm, this phone was incredibly portable. The device sported a monochrome display, which supported a resolution of 101 x 32 pixels, offering a simple yet functional interface for users to navigate. Its intuitive button layout made dialing and text input a straightforward process.

In terms of connectivity, the CMD-J16 operated on GSM technology, which was becoming increasingly popular worldwide. This allowed users to enjoy reliable voice calls and text messaging services. The device supported dual-band GSM, which provided increased coverage and versatility for international travelers.

The phone was equipped with several features that made it user-friendly. One such feature was the integrated phonebook, capable of storing up to 250 contacts. Each contact could hold multiple phone numbers and even a fax number, making it easy for users to manage their communication needs. The CMD-J16 also supported SMS messaging, allowing users to send and receive text messages seamlessly.

Another notable aspect of the CMD-J16 is its long-lasting battery life. The phone housed a NiMH battery, which offered up to 100 hours of standby time and up to 4 hours of talk time, ensuring users could stay connected for extended periods without frequent recharging.

The phone also came with a range of personalization options. Users could select from various ringtones, including polyphonic options, to customize their experience. The device allowed for basic games, adding a touch of entertainment during idle moments.

In summary, the Sony CMD-J16 was a remarkable mobile phone that combined practicality with style. Its compact design, user-friendly features, and reliable performance made it a popular choice among consumers in the late 90s. While it may now be considered a relic in the rapidly evolving world of mobile technology, the CMD-J16 remains a testament to Sony’s commitment to innovation and quality in the telecommunications landscape.